diff --git a/module/Makefile.am b/module/Makefile.am
index bae73168d..ca3852417 100644
--- a/module/Makefile.am
+++ b/module/Makefile.am
@@ -117,7 +117,6 @@ VALUE_LANG_SOURCES =				\
   language/value/spec.scm
 
 ECMASCRIPT_LANG_SOURCES =			\
-  language/ecmascript/parse-lalr.scm		\
   language/ecmascript/tokenize.scm		\
   language/ecmascript/parse.scm			\
   language/ecmascript/impl.scm			\
diff --git a/module/language/ecmascript/parse-lalr.scm b/module/language/ecmascript/parse-lalr.scm
deleted file mode 100644
index b702511ca..000000000
--- a/module/language/ecmascript/parse-lalr.scm
+++ /dev/null
@@ -1,1731 +0,0 @@
-;; (language ecmascript parse-lalr) -- yacc's parser generator, in Guile
-;; Copyright (C) 1984,1989,1990  Free Software Foundation, Inc.
-;; Copyright (C) 1996-2002  Dominique Boucher
-
-;;;; This library is free software; you can redistribute it and/or
-;;;; modify it under the terms of the GNU Lesser General Public
-;;;; License as published by the Free Software Foundation; either
-;;;; version 3 of the License, or (at your option) any later version.
-;;;; 
-;;;; This library is distributed in the hope that it will be useful,
-;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
-;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-;;;; Lesser General Public License for more details.
-;;;; 
-;;;; You should have received a copy of the GNU Lesser General Public
-;;;; License along with this library; if not, write to the Free Software
-;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
-
-
-;; ---------------------------------------------------------------------- ;;
-#!
-;;; Commentary:
-This file contains yet another LALR(1) parser generator written in     
-Scheme. In contrast to other such parser generators, this one          
-implements a more efficient algorithm for computing the lookahead sets.
-The algorithm is the same as used in Bison (GNU yacc) and is described 
-in the following paper:                                                
-
-"Efficient Computation of LALR(1) Look-Ahead Set", F. DeRemer and   
-T. Pennello, TOPLAS, vol. 4, no. 4, october 1982.                      
-
-As a consequence, it is not written in a fully functional style.       
-In fact, much of the code is a direct translation from C to Scheme     
-of the Bison sources.                                                  
-                                                                       
-@section Defining a parser                                    
-                                                                       
-The module @code{(language ecmascript parse-lalr)} declares a macro
-called @code{lalr-parser}:
-
-@lisp
-   (lalr-parser tokens rules ...)                                      
-@end lisp
-                                                                       
-This macro, when given appropriate arguments, generates an LALR(1)     
-syntax analyzer.  The macro accepts at least two arguments. The first  
-is a list of symbols which represent the terminal symbols of the       
-grammar. The remaining arguments are the grammar production rules.
-                                                                       
-@section Running the parser
-                                                                       
-The parser generated by the @code{lalr-parser} macro is a function that 
-takes two parameters. The first parameter is a lexical analyzer while  
-the second is an error procedure.                                      
-                                                                       
-The lexical analyzer is zero-argument function (a thunk)               
-invoked each time the parser needs to look-ahead in the token stream.  
-A token is usually a pair whose @code{car} is the symbol corresponding to  
-the token (the same symbol as used in the grammar definition). The     
-@code{cdr} of the pair is the semantic value associated with the token. For
-example, a string token would have the @code{car} set to @code{'string}
-while the @code{cdr} is set to the string value @code{"hello"}.      
-                                                                       
-Once the end of file is encountered, the lexical analyzer must always  
-return the symbol @code{'*eoi*} each time it is invoked.                 
-                                                                       
-The error procedure must be a function that accepts at least two        
-parameters.                                                            
-
-@section The grammar format                                 
-                                                                       
-The grammar is specified by first giving the list of terminals and the 
-list of non-terminal definitions. Each non-terminal definition         
-is a list where the first element is the non-terminal and the other    
-elements are the right-hand sides (lists of grammar symbols). In       
-addition to this, each rhs can be followed by a semantic action.       
-                                                                       
-For example, consider the following (yacc) grammar for a very simple   
-expression language:                                                   
-@example                                                              
-  e : e '+' t                                                          
-    | e '-' t                                                          
-    | t                                                                
-    ;                                                                  
-  t : t '*' f                                                          
-    : t '/' f                                                          
-    | f                                                                
-    ;                                                                  
-  f : ID                                                               
-    ;                                                                  
-@end example                                                           
-The same grammar, written for the scheme parser generator, would look  
-like this (with semantic actions)                                      
-@lisp                                                              
-(define expr-parser                                                    
-  (lalr-parser                                                         
-   ; Terminal symbols                                                  
-   (ID + - * /)                                                        
-   ; Productions                                                       
-   (e (e + t)    -> (+ $1 $3)                                           
-      (e - t)    -> (- $1 $3)                                           
-      (t)        -> $1)                                                 
-   (t (t * f)    -> (* $1 $3)                                           
-      (t / f)    -> (/ $1 $3)                                           
-      (f)        -> $1)                                                 
-   (f (ID)       -> $1)))                                               
-@end lisp                                                           
-In semantic actions, the symbol @code{$n} refers to the synthesized        
-attribute value of the nth symbol in the production. The value         
-associated with the non-terminal on the left is the result of          
-evaluating the semantic action (it defaults to @code{#f}).    
-                                                                       
-The above grammar implicitly handles operator precedences. It is also  
-possible to explicitly assign precedences and associativity to         
-terminal symbols and productions a la Yacc. Here is a modified    
-(and augmented) version of the grammar:                                
-@lisp                                                              
-(define expr-parser                                                    
- (lalr-parser                                                          
-  ; Terminal symbols                                                   
-  (ID                                                                  
-   (left: + -)                                                         
-   (left: * /)                                                         
-   (nonassoc: uminus))                                                 
-  (e (e + e)              -> (+ $1 $3)                                  
-     (e - e)              -> (- $1 $3)                                  
-     (e * e)              -> (* $1 $3)                                  
-     (e / e)              -> (/ $1 $3)                                  
-     (- e (prec: uminus)) -> (- $2)                                     
-     (ID)                 -> $1)))                                      
-@end lisp                                                           
-The @code{left:} directive is used to specify a set of left-associative    
-operators of the same precedence level, the @code{right:} directive for    
-right-associative operators, and @code{nonassoc:} for operators that       
-are not associative. Note the use of the (apparently) useless          
-terminal @code{uminus}. It is only defined in order to assign to the       
-penultimate rule a precedence level higher than that of @code{*} and  
-@code{/}. The @code{prec:} directive can only appear as the last element of a  
-rule. Finally, note that precedence levels are incremented from        
-left to right, i.e. the precedence level of @code{+} and @code{-} is less     
-than the precedence level of @code{*} and @code{/} since the formers appear    
-first in the list of terminal symbols (token definitions).             
-                                                                       
-@section A final note on conflict resolution
-                                                                       
-Conflicts in the grammar are handled in a conventional way.            
-In the absence of precedence directives,                               
-Shift/Reduce conflicts are resolved by shifting, and Reduce/Reduce     
-conflicts are resolved by choosing the rule listed first in the        
-grammar definition.                                                    
-                                                                       
-You can print the states of the generated parser by evaluating         
-@code{(print-states)}. The format of the output is similar to the one      
-produced by bison when given the -v command-line option.               
-;;; Code:
-!#
-
-;;; ---------- SYSTEM DEPENDENT SECTION -----------------
-;; put in a module by Richard Todd
-(define-module (language ecmascript parse-lalr)
-     #:export (lalr-parser
-               print-states))
-
-;; this code is by Thien-Thi Nguyen, found in a google search
-(begin
-  (defmacro def-macro (form . body)
-    `(defmacro ,(car form) ,(cdr form) ,@body))
-  (def-macro (BITS-PER-WORD) 28)
-  (def-macro (lalr-error msg obj) `(throw 'lalr-error ,msg ,obj))
-  (def-macro (logical-or x . y) `(logior ,x ,@y)))
-
-;;; ---------- END OF SYSTEM DEPENDENT SECTION ------------
-
-;; - Macros pour la gestion des vecteurs de bits
-
-(def-macro (set-bit v b)
-  `(let ((x (quotient ,b (BITS-PER-WORD)))
-	 (y (expt 2 (remainder ,b (BITS-PER-WORD)))))
-     (vector-set! ,v x (logical-or (vector-ref ,v x) y))))
-
-(def-macro (bit-union v1 v2 n)
-  `(do ((i 0 (+ i 1)))
-       ((= i ,n))
-     (vector-set! ,v1 i (logical-or (vector-ref ,v1 i) 
-				    (vector-ref ,v2 i)))))
-
-;; - Macro pour les structures de donnees
-
-(def-macro (new-core)              `(make-vector 4 0))
-(def-macro (set-core-number! c n)  `(vector-set! ,c 0 ,n))
-(def-macro (set-core-acc-sym! c s) `(vector-set! ,c 1 ,s))
-(def-macro (set-core-nitems! c n)  `(vector-set! ,c 2 ,n))
-(def-macro (set-core-items! c i)   `(vector-set! ,c 3 ,i))
-(def-macro (core-number c)         `(vector-ref ,c 0))
-(def-macro (core-acc-sym c)        `(vector-ref ,c 1))
-(def-macro (core-nitems c)         `(vector-ref ,c 2))
-(def-macro (core-items c)          `(vector-ref ,c 3))
-
-(def-macro (new-shift)              `(make-vector 3 0))
-(def-macro (set-shift-number! c x)  `(vector-set! ,c 0 ,x))
-(def-macro (set-shift-nshifts! c x) `(vector-set! ,c 1 ,x))
-(def-macro (set-shift-shifts! c x)  `(vector-set! ,c 2 ,x))
-(def-macro (shift-number s)         `(vector-ref ,s 0))
-(def-macro (shift-nshifts s)        `(vector-ref ,s 1))
-(def-macro (shift-shifts s)         `(vector-ref ,s 2))
-
-(def-macro (new-red)                `(make-vector 3 0))
-(def-macro (set-red-number! c x)    `(vector-set! ,c 0 ,x))
-(def-macro (set-red-nreds! c x)     `(vector-set! ,c 1 ,x))
-(def-macro (set-red-rules! c x)     `(vector-set! ,c 2 ,x))
-(def-macro (red-number c)           `(vector-ref ,c 0))
-(def-macro (red-nreds c)            `(vector-ref ,c 1))
-(def-macro (red-rules c)            `(vector-ref ,c 2))
-
-
-
-(def-macro (new-set nelem)
-  `(make-vector ,nelem 0))
-
-
-(def-macro (vector-map f v)
-  `(let ((vm-n (- (vector-length ,v) 1)))
-    (let loop ((vm-low 0) (vm-high vm-n))
-      (if (= vm-low vm-high)
-	  (vector-set! ,v vm-low (,f (vector-ref ,v vm-low) vm-low))
-	  (let ((vm-middle (quotient (+ vm-low vm-high) 2)))
-	    (loop vm-low vm-middle)
-	    (loop (+ vm-middle 1) vm-high))))))
-
-
-;; - Constantes
-(define STATE-TABLE-SIZE 1009)
-
-
-;; - Tableaux 
-(define rrhs         #f)
-(define rlhs         #f)
-(define ritem        #f)
-(define nullable     #f)
-(define derives      #f)
-(define fderives     #f)
-(define firsts       #f)
-(define kernel-base  #f)
-(define kernel-end   #f)
-(define shift-symbol #f)
-(define shift-set    #f)
-(define red-set      #f)
-(define state-table  #f)
-(define acces-symbol #f)
-(define reduction-table #f)
-(define shift-table  #f)
-(define consistent   #f)
-(define lookaheads   #f)
-(define LA           #f)
-(define LAruleno     #f)
-(define lookback     #f)
-(define goto-map     #f)
-(define from-state   #f)
-(define to-state     #f)
-(define includes     #f)
-(define F            #f)
-(define action-table #f)
-
-;; - Variables
-(define nitems          #f)
-(define nrules          #f)
-(define nvars           #f)
-(define nterms          #f)
-(define nsyms           #f)
-(define nstates         #f)
-(define first-state     #f)
-(define last-state      #f)
-(define final-state     #f)
-(define first-shift     #f)
-(define last-shift      #f)
-(define first-reduction #f)
-(define last-reduction  #f)
-(define nshifts         #f)
-(define maxrhs          #f)
-(define ngotos          #f)
-(define token-set-size  #f)
-
-(define (gen-tables! tokens gram)
-  (initialize-all)
-  (rewrite-grammar 
-   tokens
-   gram
-   (lambda (terms terms/prec vars gram gram/actions)
-     (set! the-terminals/prec (list->vector terms/prec))
-     (set! the-terminals (list->vector terms))
-     (set! the-nonterminals (list->vector vars))
-     (set! nterms (length terms))
-     (set! nvars  (length vars))
-     (set! nsyms  (+ nterms nvars))
-     (let ((no-of-rules (length gram/actions))
-	   (no-of-items (let loop ((l gram/actions) (count 0))
-			  (if (null? l) 
-			      count
-			      (loop (cdr l) (+ count (length (caar l))))))))
-       (pack-grammar no-of-rules no-of-items gram)
-       (set-derives)
-       (set-nullable)
-       (generate-states)
-       (lalr)
-       (build-tables)
-       (compact-action-table terms)
-       gram/actions))))
-
-
-(define (initialize-all)
-  (set! rrhs         #f)
-  (set! rlhs         #f)
-  (set! ritem        #f)
-  (set! nullable     #f)
-  (set! derives      #f)
-  (set! fderives     #f)
-  (set! firsts       #f)
-  (set! kernel-base  #f)
-  (set! kernel-end   #f)
-  (set! shift-symbol #f)
-  (set! shift-set    #f)
-  (set! red-set      #f)
-  (set! state-table  (make-vector STATE-TABLE-SIZE '()))
-  (set! acces-symbol #f)
-  (set! reduction-table #f)
-  (set! shift-table  #f)
-  (set! consistent   #f)
-  (set! lookaheads   #f)
-  (set! LA           #f)
-  (set! LAruleno     #f)
-  (set! lookback     #f)
-  (set! goto-map     #f)
-  (set! from-state   #f)
-  (set! to-state     #f)
-  (set! includes     #f)
-  (set! F            #f)
-  (set! action-table #f)
-  (set! nstates         #f)
-  (set! first-state     #f)
-  (set! last-state      #f)
-  (set! final-state     #f)
-  (set! first-shift     #f)
-  (set! last-shift      #f)
-  (set! first-reduction #f)
-  (set! last-reduction  #f)
-  (set! nshifts         #f)
-  (set! maxrhs          #f)
-  (set! ngotos          #f)
-  (set! token-set-size  #f)
-  (set! rule-precedences '()))
-
-
-(define (pack-grammar no-of-rules no-of-items gram)
-  (set! nrules (+  no-of-rules 1))
-  (set! nitems no-of-items)
-  (set! rlhs (make-vector nrules #f))
-  (set! rrhs (make-vector nrules #f))
-  (set! ritem (make-vector (+ 1 nitems) #f))
-
-  (let loop ((p gram) (item-no 0) (rule-no 1))
-	(if (not (null? p))
-	(let ((nt (caar p)))
-	  (let loop2 ((prods (cdar p)) (it-no2 item-no) (rl-no2 rule-no))
-		(if (null? prods)
-		(loop (cdr p) it-no2 rl-no2)
-		(begin
-		  (vector-set! rlhs rl-no2 nt)
-		  (vector-set! rrhs rl-no2 it-no2)
-		  (let loop3 ((rhs (car prods)) (it-no3 it-no2))
-			(if (null? rhs)
-			(begin
-			  (vector-set! ritem it-no3 (- rl-no2))
-			  (loop2 (cdr prods) (+ it-no3 1) (+ rl-no2 1)))
-			(begin
-			  (vector-set! ritem it-no3 (car rhs))
-			  (loop3 (cdr rhs) (+ it-no3 1))))))))))))
-
-
-;; Fonction set-derives
-;; --------------------
-(define (set-derives)
-  (define delts (make-vector (+ nrules 1) 0))
-  (define dset  (make-vector nvars -1))
-
-  (let loop ((i 1) (j 0))		; i = 0
-    (if (< i nrules)
-	(let ((lhs (vector-ref rlhs i)))
-	  (if (>= lhs 0)
-	      (begin
-		(vector-set! delts j (cons i (vector-ref dset lhs)))
-		(vector-set! dset lhs j)
-		(loop (+ i 1) (+ j 1)))
-	      (loop (+ i 1) j)))))
-  
-  (set! derives (make-vector nvars 0))
-  
-  (let loop ((i 0))
-    (if (< i nvars)
-	(let ((q (let loop2 ((j (vector-ref dset i)) (s '()))
-		   (if (< j 0)
-		       s
-		       (let ((x (vector-ref delts j)))
-			 (loop2 (cdr x) (cons (car x) s)))))))
-	  (vector-set! derives i q)
-	  (loop (+ i 1))))))
-
-
-
-(define (set-nullable)
-  (set! nullable (make-vector nvars #f))
-  (let ((squeue (make-vector nvars #f))
-	(rcount (make-vector (+ nrules 1) 0))
-	(rsets  (make-vector nvars #f))
-	(relts  (make-vector (+ nitems nvars 1) #f)))
-    (let loop ((r 0) (s2 0) (p 0))
-      (let ((*r (vector-ref ritem r)))
-	(if *r
-	    (if (< *r 0)
-		(let ((symbol (vector-ref rlhs (- *r))))
-		  (if (and (>= symbol 0)
-			   (not (vector-ref nullable symbol)))
-		      (begin
-			(vector-set! nullable symbol #t)
-			(vector-set! squeue s2 symbol)
-			(loop (+ r 1) (+ s2 1) p))))
-		(let loop2 ((r1 r) (any-tokens #f))
-		  (let* ((symbol (vector-ref ritem r1)))
-		    (if (> symbol 0)
-			(loop2 (+ r1 1) (or any-tokens (>= symbol nvars)))
-			(if (not any-tokens)
-			    (let ((ruleno (- symbol)))
-			      (let loop3 ((r2 r) (p2 p))
-				(let ((symbol (vector-ref ritem r2)))
-				  (if (> symbol 0)
-				      (begin
-					(vector-set! rcount ruleno
-						     (+ (vector-ref rcount ruleno) 1))
-					(vector-set! relts p2
-						     (cons (vector-ref rsets symbol)
-							   ruleno))
-					(vector-set! rsets symbol p2)
-					(loop3 (+ r2 1) (+ p2 1)))
-				      (loop (+ r2 1) s2 p2)))))
-			    (loop (+ r1 1) s2 p))))))
-	    (let loop ((s1 0) (s3 s2))
-	      (if (< s1 s3)
-		  (let loop2 ((p (vector-ref rsets (vector-ref squeue s1))) (s4 s3))
-		    (if p 
-			(let* ((x (vector-ref relts p))
-			       (ruleno (cdr x))
-			       (y (- (vector-ref rcount ruleno) 1)))
-			  (vector-set! rcount ruleno y)
-			  (if (= y 0)
-			      (let ((symbol (vector-ref rlhs ruleno)))
-				(if (and (>= symbol 0)
-					 (not (vector-ref nullable symbol)))
-				    (begin
-				      (vector-set! nullable symbol #t)
-				      (vector-set! squeue s4 symbol)
-				      (loop2 (car x) (+ s4 1)))
-				    (loop2 (car x) s4)))
-			      (loop2 (car x) s4))))
-		    (loop (+ s1 1) s4)))))))))
-		  
-
-
-; Fonction set-firsts qui calcule un tableau de taille
-; nvars et qui donne, pour chaque non-terminal X, une liste des
-; non-terminaux pouvant apparaitre au debut d'une derivation a
-; partir de X.
-
-(define (set-firsts)
-  (set! firsts (make-vector nvars '()))
-  
-  ;; -- initialization
-  (let loop ((i 0))
-    (if (< i nvars)
-	(let loop2 ((sp (vector-ref derives i)))
-	  (if (null? sp)
-	      (loop (+ i 1))
-	      (let ((sym (vector-ref ritem (vector-ref rrhs (car sp)))))
-		(if (< -1 sym nvars)
-		    (vector-set! firsts i (sinsert sym (vector-ref firsts i))))
-		(loop2 (cdr sp)))))))
-
-  ;; -- reflexive and transitive closure
-  (let loop ((continue #t))
-    (if continue
-	(let loop2 ((i 0) (cont #f))
-	  (if (>= i nvars)
-	      (loop cont)
-	      (let* ((x (vector-ref firsts i))
-		     (y (let loop3 ((l x) (z x))
-			  (if (null? l)
-			      z
-			      (loop3 (cdr l)
-				     (sunion (vector-ref firsts (car l)) z))))))
-		(if (equal? x y)
-		    (loop2 (+ i 1) cont)
-		    (begin
-		      (vector-set! firsts i y)
-		      (loop2 (+ i 1) #t))))))))
-  
-  (let loop ((i 0))
-    (if (< i nvars)
-	(begin
-	  (vector-set! firsts i (sinsert i (vector-ref firsts i)))
-	  (loop (+ i 1))))))
-
-
-
-
-; Fonction set-fderives qui calcule un tableau de taille
-; nvars et qui donne, pour chaque non-terminal, une liste des regles pouvant
-; etre derivees a partir de ce non-terminal. (se sert de firsts)
-
-(define (set-fderives)
-  (set! fderives (make-vector nvars #f))
-
-  (set-firsts)
-
-  (let loop ((i 0))
-    (if (< i nvars)
-	(let ((x (let loop2 ((l (vector-ref firsts i)) (fd '()))
-		   (if (null? l) 
-		       fd
-		       (loop2 (cdr l) 
-			      (sunion (vector-ref derives (car l)) fd))))))
-	  (vector-set! fderives i x)
-	  (loop (+ i 1))))))
-
-
-; Fonction calculant la fermeture d'un ensemble d'items LR0
-; ou core est une liste d'items
-
-(define (closure core)
-  ;; Initialization
-  (define ruleset (make-vector nrules #f))
-
-  (let loop ((csp core))
-    (if (not (null? csp))
-	(let ((sym (vector-ref ritem (car csp))))
-	  (if (< -1 sym nvars)
-	      (let loop2 ((dsp (vector-ref fderives sym)))
-		(if (not (null? dsp))
-		    (begin
-		      (vector-set! ruleset (car dsp) #t)
-		      (loop2 (cdr dsp))))))
-	  (loop (cdr csp)))))
-
-  (let loop ((ruleno 1) (csp core) (itemsetv '())) ; ruleno = 0
-    (if (< ruleno nrules)
-	(if (vector-ref ruleset ruleno)
-	    (let ((itemno (vector-ref rrhs ruleno)))
-	      (let loop2 ((c csp) (itemsetv2 itemsetv))
-		(if (and (pair? c)
-			 (< (car c) itemno))
-		    (loop2 (cdr c) (cons (car c) itemsetv2))
-		    (loop (+ ruleno 1) c (cons itemno itemsetv2)))))
-	    (loop (+ ruleno 1) csp itemsetv))
-	(let loop2 ((c csp) (itemsetv2 itemsetv))
-	  (if (pair? c)
-	      (loop2 (cdr c) (cons (car c) itemsetv2))
-	      (reverse itemsetv2))))))
-
-
-
-(define (allocate-item-sets)
-  (set! kernel-base (make-vector nsyms 0))
-  (set! kernel-end  (make-vector nsyms #f)))
-
-
-(define (allocate-storage)
-  (allocate-item-sets)
-  (set! red-set (make-vector (+ nrules 1) 0)))
-
-;; --
-
-
-(define (initialize-states)
-  (let ((p (new-core)))
-    (set-core-number! p 0)
-    (set-core-acc-sym! p #f)
-    (set-core-nitems! p 1)
-    (set-core-items! p '(0))
-
-    (set! first-state (list p))
-    (set! last-state first-state)
-    (set! nstates 1)))
-
-
-
-(define (generate-states)
-  (allocate-storage)
-  (set-fderives)
-  (initialize-states)
-  (let loop ((this-state first-state))
-    (if (pair? this-state)
-	(let* ((x (car this-state))
-	       (is (closure (core-items x))))
-	  (save-reductions x is)
-	  (new-itemsets is)
-	  (append-states)
-	  (if (> nshifts 0)
-	      (save-shifts x))
-	  (loop (cdr this-state))))))
-
-
-;; Fonction calculant les symboles sur lesquels il faut "shifter" 
-;; et regroupe les items en fonction de ces symboles
-
-(define (new-itemsets itemset)
-  ;; - Initialization
-  (set! shift-symbol '())
-  (let loop ((i 0))
-    (if (< i nsyms)
-	(begin
-	  (vector-set! kernel-end i '())
-	  (loop (+ i 1)))))
-
-  (let loop ((isp itemset))
-    (if (pair? isp)
-	(let* ((i (car isp))
-	       (sym (vector-ref ritem i)))
-	  (if (>= sym 0)
-	      (begin
-		(set! shift-symbol (sinsert sym shift-symbol))
-		(let ((x (vector-ref kernel-end sym)))
-		  (if (null? x)
-		      (begin
-			(vector-set! kernel-base sym (cons (+ i 1) x))
-			(vector-set! kernel-end sym (vector-ref kernel-base sym)))
-		      (begin
-			(set-cdr! x (list (+ i 1)))
-			(vector-set! kernel-end sym (cdr x)))))))
-	  (loop (cdr isp)))))
-
-  (set! nshifts (length shift-symbol)))
-
-
-
-(define (get-state sym)
-  (let* ((isp  (vector-ref kernel-base sym))
-	 (n    (length isp))
-	 (key  (let loop ((isp1 isp) (k 0))
-		 (if (null? isp1)
-		     (modulo k STATE-TABLE-SIZE)
-		     (loop (cdr isp1) (+ k (car isp1))))))
-	 (sp   (vector-ref state-table key)))
-    (if (null? sp)
-	(let ((x (new-state sym)))
-	  (vector-set! state-table key (list x))
-	  (core-number x))
-	(let loop ((sp1 sp))
-	  (if (and (= n (core-nitems (car sp1)))
-		   (let loop2 ((i1 isp) (t (core-items (car sp1)))) 
-		     (if (and (pair? i1) 
-			      (= (car i1)
-				 (car t)))
-			 (loop2 (cdr i1) (cdr t))
-			 (null? i1))))
-	      (core-number (car sp1))
-	      (if (null? (cdr sp1))
-		  (let ((x (new-state sym)))
-		    (set-cdr! sp1 (list x))
-		    (core-number x))
-		  (loop (cdr sp1))))))))
-
-
-(define (new-state sym)
-  (let* ((isp  (vector-ref kernel-base sym))
-	 (n    (length isp))
-	 (p    (new-core)))
-    (set-core-number! p nstates)
-    (set-core-acc-sym! p sym)
-    (if (= sym nvars) (set! final-state nstates))
-    (set-core-nitems! p n)
-    (set-core-items! p isp)
-    (set-cdr! last-state (list p))
-    (set! last-state (cdr last-state))
-    (set! nstates (+ nstates 1))
-    p))
-
-
-;; --
-
-(define (append-states)
-  (set! shift-set
-	(let loop ((l (reverse shift-symbol)))
-	  (if (null? l)
-	      '()
-	      (cons (get-state (car l)) (loop (cdr l)))))))
-
-;; --
-
-(define (save-shifts core)
-  (let ((p (new-shift)))
-	(set-shift-number! p (core-number core))
-	(set-shift-nshifts! p nshifts)
-	(set-shift-shifts! p shift-set)
-	(if last-shift
-	(begin
-	  (set-cdr! last-shift (list p))
-	  (set! last-shift (cdr last-shift)))
-	(begin
-	  (set! first-shift (list p))
-	  (set! last-shift first-shift)))))
-
-(define (save-reductions core itemset)
-  (let ((rs (let loop ((l itemset))
-	      (if (null? l)
-		  '()
-		  (let ((item (vector-ref ritem (car l))))
-		    (if (< item 0)
-			(cons (- item) (loop (cdr l)))
-			(loop (cdr l))))))))
-    (if (pair? rs)
-	(let ((p (new-red)))
-	  (set-red-number! p (core-number core))
-	  (set-red-nreds!  p (length rs))
-	  (set-red-rules!  p rs)
-	  (if last-reduction
-	      (begin
-		(set-cdr! last-reduction (list p))
-		(set! last-reduction (cdr last-reduction)))
-	      (begin
-		(set! first-reduction (list p))
-		(set! last-reduction first-reduction)))))))
-
-
-;; --
-
-(define (lalr)
-  (set! token-set-size (+ 1 (quotient nterms (BITS-PER-WORD))))
-  (set-accessing-symbol)
-  (set-shift-table)
-  (set-reduction-table)
-  (set-max-rhs)
-  (initialize-LA)
-  (set-goto-map)
-  (initialize-F)
-  (build-relations)
-  (digraph includes)
-  (compute-lookaheads))
-
-(define (set-accessing-symbol)
-  (set! acces-symbol (make-vector nstates #f))
-  (let loop ((l first-state))
-    (if (pair? l)
-	(let ((x (car l)))
-	  (vector-set! acces-symbol (core-number x) (core-acc-sym x))
-	  (loop (cdr l))))))
-
-(define (set-shift-table)
-  (set! shift-table (make-vector nstates #f))
-  (let loop ((l first-shift))
-    (if (pair? l)
-	(let ((x (car l)))
-	  (vector-set! shift-table (shift-number x) x)
-	  (loop (cdr l))))))
-
-(define (set-reduction-table)
-  (set! reduction-table (make-vector nstates #f))
-  (let loop ((l first-reduction))
-    (if (pair? l)
-	(let ((x (car l)))
-	  (vector-set! reduction-table (red-number x) x)
-	  (loop (cdr l))))))
-
-(define (set-max-rhs)
-  (let loop ((p 0) (curmax 0) (length 0))
-    (let ((x (vector-ref ritem p)))
-      (if x
-	  (if (>= x 0)
-	      (loop (+ p 1) curmax (+ length 1))
-	      (loop (+ p 1) (max curmax length) 0))
-	  (set! maxrhs curmax)))))
-
-(define (initialize-LA)
-  (define (last l)
-    (if (null? (cdr l))
-	(car l)
-	(last (cdr l))))
-
-  (set! consistent (make-vector nstates #f))
-  (set! lookaheads (make-vector (+ nstates 1) #f))
-
-  (let loop ((count 0) (i 0))
-    (if (< i nstates)
-	(begin
-	  (vector-set! lookaheads i count)
-	  (let ((rp (vector-ref reduction-table i))
-		(sp (vector-ref shift-table i)))
-	    (if (and rp
-		     (or (> (red-nreds rp) 1)
-			 (and sp
-			      (not
-			       (< (vector-ref acces-symbol
-					      (last (shift-shifts sp)))
-				  nvars)))))
-		(loop (+ count (red-nreds rp)) (+ i 1))
-		(begin
-		  (vector-set! consistent i #t)
-		  (loop count (+ i 1))))))
-
-	(begin
-	  (vector-set! lookaheads nstates count)
-	  (let ((c (max count 1)))
-	    (set! LA (make-vector c #f))
-	    (do ((j 0 (+ j 1))) ((= j c)) (vector-set! LA j (new-set token-set-size)))
-	    (set! LAruleno (make-vector c -1))
-	    (set! lookback (make-vector c #f)))
-	  (let loop ((i 0) (np 0))
-	    (if (< i nstates)
-		(if (vector-ref consistent i)
-		    (loop (+ i 1) np)
-		    (let ((rp (vector-ref reduction-table i)))
-		      (if rp
-			  (let loop2 ((j (red-rules rp)) (np2 np))
-			    (if (null? j)
-				(loop (+ i 1) np2)
-				(begin
-				  (vector-set! LAruleno np2 (car j))
-				  (loop2 (cdr j) (+ np2 1)))))
-			  (loop (+ i 1) np))))))))))
-
-
-(define (set-goto-map)
-  (set! goto-map (make-vector (+ nvars 1) 0))
-  (let ((temp-map (make-vector (+ nvars 1) 0)))
-    (let loop ((ng 0) (sp first-shift))
-      (if (pair? sp)
-	  (let loop2 ((i (reverse (shift-shifts (car sp)))) (ng2 ng))
-	    (if (pair? i)
-		(let ((symbol (vector-ref acces-symbol (car i))))
-		  (if (< symbol nvars)
-		      (begin
-			(vector-set! goto-map symbol 
-				     (+ 1 (vector-ref goto-map symbol)))
-			(loop2 (cdr i) (+ ng2 1)))
-		      (loop2 (cdr i) ng2)))
-		(loop ng2 (cdr sp))))
-
-	  (let loop ((k 0) (i 0))
-	    (if (< i nvars)
-		(begin
-		  (vector-set! temp-map i k)
-		  (loop (+ k (vector-ref goto-map i)) (+ i 1)))
-
-		(begin
-		  (do ((i 0 (+ i 1)))
-		      ((>= i nvars))
-		    (vector-set! goto-map i (vector-ref temp-map i)))
-
-		  (set! ngotos ng)
-		  (vector-set! goto-map nvars ngotos)
-		  (vector-set! temp-map nvars ngotos)
-		  (set! from-state (make-vector ngotos #f))
-		  (set! to-state (make-vector ngotos #f))
-		  
-		  (do ((sp first-shift (cdr sp)))
-		      ((null? sp))
-		    (let* ((x (car sp))
-			   (state1 (shift-number x)))
-		      (do ((i (shift-shifts x) (cdr i)))
-			  ((null? i))
-			(let* ((state2 (car i))
-			       (symbol (vector-ref acces-symbol state2)))
-			  (if (< symbol nvars)
-			      (let ((k (vector-ref temp-map symbol)))
-				(vector-set! temp-map symbol (+ k 1))
-				(vector-set! from-state k state1)
-				(vector-set! to-state k state2))))))))))))))
-
-
-(define (map-goto state symbol)
-  (let loop ((low (vector-ref goto-map symbol))
-	     (high (- (vector-ref goto-map (+ symbol 1)) 1)))
-    (if (> low high)
-	(begin
-	  (display (list "Error in map-goto" state symbol) (current-error-port))
-          (newline (current-error-port))
-	  0)
-	(let* ((middle (quotient (+ low high) 2))
-	       (s (vector-ref from-state middle)))
-	  (cond
-	   ((= s state)
-	    middle)
-	   ((< s state)
-	    (loop (+ middle 1) high))
-	   (else
-	    (loop low (- middle 1))))))))
-
-
-(define (initialize-F)
-  (set! F (make-vector ngotos #f))
-  (do ((i 0 (+ i 1))) ((= i ngotos)) (vector-set! F i (new-set token-set-size)))
-
-  (let ((reads (make-vector ngotos #f)))
-
-    (let loop ((i 0) (rowp 0))
-      (if (< i ngotos)
-	  (let* ((rowf (vector-ref F rowp))
-		 (stateno (vector-ref to-state i))
-		 (sp (vector-ref shift-table stateno)))
-	    (if sp
-		(let loop2 ((j (shift-shifts sp)) (edges '()))
-		  (if (pair? j)
-		      (let ((symbol (vector-ref acces-symbol (car j))))
-			(if (< symbol nvars)
-			    (if (vector-ref nullable symbol)
-				(loop2 (cdr j) (cons (map-goto stateno symbol) 
-						     edges))
-				(loop2 (cdr j) edges))
-			    (begin
-			      (set-bit rowf (- symbol nvars))
-			      (loop2 (cdr j) edges))))
-		      (if (pair? edges)
-			  (vector-set! reads i (reverse edges))))))
-	      (loop (+ i 1) (+ rowp 1)))))
-    (digraph reads)))
-
-(define (add-lookback-edge stateno ruleno gotono)
-  (let ((k (vector-ref lookaheads (+ stateno 1))))
-    (let loop ((found #f) (i (vector-ref lookaheads stateno)))
-      (if (and (not found) (< i k))
-	  (if (= (vector-ref LAruleno i) ruleno)
-	      (loop #t i)
-	      (loop found (+ i 1)))
-
-	  (if (not found)
-	      (begin (display "Error in add-lookback-edge : " (current-error-port))
-		     (display (list stateno ruleno gotono) (current-error-port))
-                     (newline (current-error-port)))
-	      (vector-set! lookback i
-			   (cons gotono (vector-ref lookback i))))))))
-
-
-(define (transpose r-arg n)
-  (let ((new-end (make-vector n #f))
-	(new-R  (make-vector n #f)))
-    (do ((i 0 (+ i 1))) 
-	((= i n))
-      (let ((x (list 'bidon)))
-	(vector-set! new-R i x)
-	(vector-set! new-end i x)))
-    (do ((i 0 (+ i 1)))
-	((= i n))
-      (let ((sp (vector-ref r-arg i)))
-	(if (pair? sp)
-	    (let loop ((sp2 sp))
-	      (if (pair? sp2)
-		  (let* ((x (car sp2))
-			 (y (vector-ref new-end x)))
-		    (set-cdr! y (cons i (cdr y)))
-		    (vector-set! new-end x (cdr y))
-		    (loop (cdr sp2))))))))
-    (do ((i 0 (+ i 1)))
-	((= i n))
-      (vector-set! new-R i (cdr (vector-ref new-R i))))
-    
-    new-R))
-
-
-
-(define (build-relations)
-
-  (define (get-state stateno symbol)
-    (let loop ((j (shift-shifts (vector-ref shift-table stateno)))
-	       (stno stateno))
-      (if (null? j)
-	  stno
-	  (let ((st2 (car j)))
-	    (if (= (vector-ref acces-symbol st2) symbol)
-		st2
-		(loop (cdr j) st2))))))
-
-  (set! includes (make-vector ngotos #f))
-  (do ((i 0 (+ i 1)))
-      ((= i ngotos))
-    (let ((state1 (vector-ref from-state i))
-	  (symbol1 (vector-ref acces-symbol (vector-ref to-state i))))
-      (let loop ((rulep (vector-ref derives symbol1))
-		 (edges '()))
-	(if (pair? rulep)
-	    (let ((*rulep (car rulep)))
-	      (let loop2 ((rp (vector-ref rrhs *rulep))
-			  (stateno state1)
-			  (states (list state1)))
-		(let ((*rp (vector-ref ritem rp)))
-		  (if (> *rp 0)
-		      (let ((st (get-state stateno *rp)))
-			(loop2 (+ rp 1) st (cons st states)))
-		      (begin
-
-			(if (not (vector-ref consistent stateno))
-			    (add-lookback-edge stateno *rulep i))
-			
-			(let loop2 ((done #f) 
-				    (stp (cdr states))
-				    (rp2 (- rp 1))
-				    (edgp edges))
-			  (if (not done)
-			      (let ((*rp (vector-ref ritem rp2)))
-				(if (< -1 *rp nvars)
-				  (loop2 (not (vector-ref nullable *rp))
-					 (cdr stp)
-					 (- rp2 1)
-					 (cons (map-goto (car stp) *rp) edgp))
-				  (loop2 #t stp rp2 edgp)))
-
-			      (loop (cdr rulep) edgp))))))))
-	    (vector-set! includes i edges)))))
-  (set! includes (transpose includes ngotos)))
-			
-
-
-(define (compute-lookaheads)
-  (let ((n (vector-ref lookaheads nstates)))
-    (let loop ((i 0))
-      (if (< i n)
-	  (let loop2 ((sp (vector-ref lookback i)))
-	    (if (pair? sp)
-		(let ((LA-i (vector-ref LA i))
-		      (F-j  (vector-ref F (car sp))))
-		  (bit-union LA-i F-j token-set-size)
-		  (loop2 (cdr sp)))
-		(loop (+ i 1))))))))
-
-
-
-(define (digraph relation)
-  (define infinity (+ ngotos 2))
-  (define INDEX (make-vector (+ ngotos 1) 0))
-  (define VERTICES (make-vector (+ ngotos 1) 0))
-  (define top 0)
-  (define R relation)
-
-  (define (traverse i)
-    (set! top (+ 1 top))
-    (vector-set! VERTICES top i)
-    (let ((height top))
-      (vector-set! INDEX i height)
-      (let ((rp (vector-ref R i)))
-	(if (pair? rp)
-	    (let loop ((rp2 rp))
-	      (if (pair? rp2)
-		  (let ((j (car rp2)))
-		    (if (= 0 (vector-ref INDEX j))
-			(traverse j))
-		    (if (> (vector-ref INDEX i) 
-			   (vector-ref INDEX j))
-			(vector-set! INDEX i (vector-ref INDEX j)))
-		    (let ((F-i (vector-ref F i))
-			  (F-j (vector-ref F j)))
-		      (bit-union F-i F-j token-set-size))
-		    (loop (cdr rp2))))))
-	(if (= (vector-ref INDEX i) height)
-	    (let loop ()
-	      (let ((j (vector-ref VERTICES top)))
-		(set! top (- top 1))
-		(vector-set! INDEX j infinity)
-		(if (not (= i j))
-		    (begin
-		      (bit-union (vector-ref F i) 
-				 (vector-ref F j)
-				 token-set-size)
-		      (loop)))))))))
-
-  (let loop ((i 0))
-    (if (< i ngotos)
-	(begin
-	  (if (and (= 0 (vector-ref INDEX i))
-		   (pair? (vector-ref R i)))
-	      (traverse i))
-	  (loop (+ i 1))))))
-
-
-;; ---------------------------------------------------------------------- ;;
-;; operator precedence management                                         ;;
-;; ---------------------------------------------------------------------- ;;
-
-; a vector of precedence descriptors where each element
-; is of the form (terminal type precedence)
-(define the-terminals/prec #f)		; terminal symbols with precedence 
-; the precedence is an integer >= 0
-(define (get-symbol-precedence sym)
-  (caddr (vector-ref the-terminals/prec sym)))
-; the operator type is either 'none, 'left, 'right, or 'nonassoc
-(define (get-symbol-assoc sym)
-  (cadr (vector-ref the-terminals/prec sym)))
-
-(define rule-precedences '())
-(define (add-rule-precedence! rule sym)
-  (set! rule-precedences
-	(cons (cons rule sym) rule-precedences)))
-
-(define (get-rule-precedence ruleno)
-  (cond
-   ((assq ruleno rule-precedences) 
-    => (lambda (p) 
-	 (get-symbol-precedence (cdr p))))
-   (else
-    ;; process the rule symbols from left to right
-    (let loop ((i    (vector-ref rrhs ruleno))
-	       (prec 0))
-      (let ((item (vector-ref ritem i)))
-	;; end of rule
-	(if (< item 0)
-	    prec
-	    (let ((i1 (+ i 1)))
-	      (if (>= item nvars)
-		  ;; it's a terminal symbol
-		  (loop i1 (get-symbol-precedence (- item nvars)))
-		  (loop i1 prec)))))))))
-
-;; ---------------------------------------------------------------------- ;;
-;; Build the various tables                                               ;;
-;; ---------------------------------------------------------------------- ;;
-(define (build-tables)
-  
-  (define (resolve-conflict sym rule)
-    (let ((sym-prec   (get-symbol-precedence sym))
-	  (sym-assoc  (get-symbol-assoc sym))
-	  (rule-prec  (get-rule-precedence rule)))
-      (cond
-       ((> sym-prec rule-prec)     'shift)
-       ((< sym-prec rule-prec)     'reduce)
-       ((eq? sym-assoc 'left)      'reduce)
-       ((eq? sym-assoc 'right)     'shift)
-       (else                       'shift))))
-	
-  ;; --- Add an action to the action table ------------------------------ ;;
-  (define (add-action St Sym Act)
-    (let* ((x (vector-ref action-table St))
-	   (y (assv Sym x)))
-      (if y
-	  (if (not (= Act (cdr y)))
-	      ;; -- there is a conflict 
-	      (begin
-		(if (and (<= (cdr y) 0)
-			 (<= Act 0))
-		    ;; --- reduce/reduce conflict ----------------------- ;;
-		    (begin
-		      (display "%% Reduce/Reduce conflict " (current-error-port))
-		      (display "(reduce "  (current-error-port))
-                      (display (- Act) (current-error-port))
-		      (display ", reduce " (current-error-port))
-                      (display (- (cdr y)) (current-error-port))
-		      (display ") on " (current-error-port))
-                      (print-symbol (+ Sym nvars) (current-error-port))
-		      (display " in state "  (current-error-port))
-                      (display St (current-error-port))
-		      (newline (current-error-port))
-		      (set-cdr! y (max (cdr y) Act)))
-		    ;; --- shift/reduce conflict ------------------------ ;;
-		    ;; can we resolve the conflict using precedences?
-		    (case (resolve-conflict Sym (- (cdr y)))
-		      ;; -- shift
-		      ((shift)
-		       (set-cdr! y Act))
-		      ;; -- reduce
-		      ((reduce)
-		       #f)		; well, nothing to do...
-		      ;; -- signal a conflict!
-		      (else
-		       (display "%% Shift/Reduce conflict " (current-error-port))
-		       (display "(shift " (current-error-port))
-                       (display Act (current-error-port))
-		       (display ", reduce " (current-error-port))
-                       (display (- (cdr y)) (current-error-port))
-		       (display ") on " (current-error-port))
-                       (print-symbol (+ Sym nvars) (current-error-port))
-		       (display " in state " (current-error-port))
-                       (display St (current-error-port))
-		       (newline (current-error-port))
-		       (set-cdr! y Act))))))
-	  
-	  (vector-set! action-table St (cons (cons Sym Act) x)))))
-	
-  (set! action-table (make-vector nstates '()))
-
-  (do ((i 0 (+ i 1)))  ; i = state
-      ((= i nstates))
-    (let ((red (vector-ref reduction-table i)))
-      (if (and red (>= (red-nreds red) 1))
-	  (if (and (= (red-nreds red) 1) (vector-ref consistent i))
-	      (add-action i 'default (- (car (red-rules red))))
-	      (let ((k (vector-ref lookaheads (+ i 1))))
-		(let loop ((j (vector-ref lookaheads i)))
-		  (if (< j k)
-		      (let ((rule (- (vector-ref LAruleno j)))
-			    (lav  (vector-ref LA j)))
-			(let loop2 ((token 0) (x (vector-ref lav 0)) (y 1) (z 0))
-			  (if (< token nterms)
-			      (begin
-				(let ((in-la-set? (modulo x 2)))
-				  (if (= in-la-set? 1)
-				      (add-action i token rule)))
-				(if (= y (BITS-PER-WORD))
-				    (loop2 (+ token 1) 
-					   (vector-ref lav (+ z 1))
-					   1
-					   (+ z 1))
-				    (loop2 (+ token 1) (quotient x 2) (+ y 1) z)))))
-			(loop (+ j 1)))))))))
-
-    (let ((shiftp (vector-ref shift-table i)))
-      (if shiftp
-	  (let loop ((k (shift-shifts shiftp)))
-	    (if (pair? k)
-		(let* ((state (car k))
-		       (symbol (vector-ref acces-symbol state)))
-		  (if (>= symbol nvars)
-		      (add-action i (- symbol nvars) state))
-		  (loop (cdr k))))))))
-
-  (add-action final-state 0 'accept))
-
-(define (compact-action-table terms)
-  (define (most-common-action acts)
-    (let ((accums '()))
-      (let loop ((l acts))
-	(if (pair? l)
-	    (let* ((x (cdar l))
-		   (y (assv x accums)))
-	      (if (and (number? x) (< x 0))
-		  (if y
-		      (set-cdr! y (+ 1 (cdr y)))
-		      (set! accums (cons `(,x . 1) accums))))
-	      (loop (cdr l)))))
-
-      (let loop ((l accums) (max 0) (sym #f))
-	(if (null? l)
-	    sym
-	    (let ((x (car l)))
-	      (if (> (cdr x) max)
-		  (loop (cdr l) (cdr x) (car x))
-		  (loop (cdr l) max sym)))))))
-  
-  (define (translate-terms acts)
-    (map (lambda (act) 
-	   (cons (list-ref terms (car act))
-		 (cdr act)))
-	 acts))
-
-  (do ((i 0 (+ i 1)))
-      ((= i nstates))
-    (let ((acts (vector-ref action-table i)))
-      (if (vector? (vector-ref reduction-table i))
-	  (let ((act (most-common-action acts)))
-	    (vector-set! action-table i
-			 (cons `(*default* . ,(if act act 'error))
-			       (translate-terms
-				(lalr-filter (lambda (x) 
-					  (not (eq? (cdr x) act)))
-					acts)))))
-	  (vector-set! action-table i 
-		       (cons `(*default* . *error*) 
-			     (translate-terms acts)))))))
-
-
-
-;; --
-
-(define (rewrite-grammar tokens grammar k) 
-
-  (define eoi '*eoi*)
-  
-  (define (check-terminal term terms)
-    (cond 
-     ((not (valid-terminal? term))
-      (lalr-error "invalid terminal: " term))
-     ((member term terms)
-      (lalr-error "duplicate definition of terminal: " term))))
-  
-  (define (prec->type prec)
-    (cdr (assq prec '((left:     . left) 
-		      (right:    . right)
-		      (nonassoc: . nonassoc)))))
-
-  (cond
-   ;; --- a few error conditions ---------------------------------------- ;;
-   ((not (list? tokens))
-    (lalr-error "Invalid token list: " tokens))
-   ((not (pair? grammar))
-    (lalr-error "Grammar definition must have a non-empty list of productions" '()))
-   
-   (else
-    ;; --- check the terminals ---------------------------------------- ;;
-    (let loop1 ((lst            tokens)
-		(rev-terms      '())
-		(rev-terms/prec '())
-		(prec-level     0))
-      (if (pair? lst)
-	  (let ((term (car lst)))
-	    (cond
-	     ((pair? term)
-	      (if (and (memq (car term) '(left: right: nonassoc:))
-		       (not (null? (cdr term))))
-		  (let ((prec    (+ prec-level 1))
-			(optype  (prec->type (car term))))
-		    (let loop-toks ((l             (cdr term))
-				    (rev-terms      rev-terms)
-				    (rev-terms/prec rev-terms/prec))
-		      (if (null? l)
-			  (loop1 (cdr lst) rev-terms rev-terms/prec prec)
-			  (let ((term (car l)))
-			    (check-terminal term rev-terms)
-			    (loop-toks 
-			     (cdr l)
-			     (cons term rev-terms)
-			     (cons (list term optype prec) rev-terms/prec))))))
-		  
-		  (lalr-error "invalid operator precedence specification: " term)))
-	      
-	     (else
-	      (check-terminal term rev-terms)
-	      (loop1 (cdr lst) 
-		     (cons term rev-terms)
-		     (cons (list term 'none 0) rev-terms/prec)
-		     prec-level))))
-	  
-	  ;; --- check the grammar rules ------------------------------ ;;
-	  (let loop2 ((lst grammar) (rev-nonterm-defs '()))
-	    (if (pair? lst)
-		(let ((def (car lst)))
-		  (if (not (pair? def))
-		      (lalr-error "Nonterminal definition must be a non-empty list" '())
-		      (let ((nonterm (car def)))
-			(cond ((not (valid-nonterminal? nonterm))
-			       (lalr-error "Invalid nonterminal:" nonterm))
-			      ((or (member nonterm rev-terms)
-				   (assoc nonterm rev-nonterm-defs))
-			       (lalr-error "Nonterminal previously defined:" nonterm))
-			      (else
-			       (loop2 (cdr lst)
-				      (cons def rev-nonterm-defs)))))))
-		(let* ((terms        (cons eoi (reverse rev-terms)))
-		       (terms/prec   (cons '(eoi none 0) (reverse rev-terms/prec)))
-		       (nonterm-defs (reverse rev-nonterm-defs))
-		       (nonterms     (cons '*start* (map car nonterm-defs))))
-		  (if (= (length nonterms) 1)
-		      (lalr-error "Grammar must contain at least one nonterminal" '())
-		      (let loop-defs ((defs      (cons `(*start* (,(cadr nonterms) ,eoi) -> $1)
-						       nonterm-defs))
-				      (ruleno    0)
-				      (comp-defs '()))
-			(if (pair? defs)
-			    (let* ((nonterm-def  (car defs))
-				   (compiled-def (rewrite-nonterm-def 
-						  nonterm-def 
-						  ruleno
-						  terms nonterms)))
-			      (loop-defs (cdr defs)
-					 (+ ruleno (length compiled-def))
-					 (cons compiled-def comp-defs)))
-
-			    (let ((compiled-nonterm-defs (reverse comp-defs)))
-			      (k terms
-				 terms/prec
-				 nonterms
-				 (map (lambda (x) (cons (caaar x) (map cdar x)))
-				      compiled-nonterm-defs)
-				 (apply append compiled-nonterm-defs))))))))))))))
-
-
-(define *arrow* '->)
-
-(define (rewrite-nonterm-def nonterm-def ruleno terms nonterms)
-
-  (define No-NT (length nonterms))
-
-  (define (encode x) 
-    (let ((PosInNT (pos-in-list x nonterms)))
-      (if PosInNT
-	  PosInNT
-	  (let ((PosInT (pos-in-list x terms)))
-	    (if PosInT
-		(+ No-NT PosInT)
-		(lalr-error "undefined symbol : " x))))))
-  
-  (define (process-prec-directive rhs ruleno)
-    (let loop ((l rhs))
-      (if (null? l) 
-	  '()
-	  (let ((first (car l))
-		(rest  (cdr l)))
-	    (cond
-	     ((or (member first terms) (member first nonterms))
-	      (cons first (loop rest)))
-	     ((and (pair? first)
-		   (eq? (car first) 'prec:))
-		   (pair? (cdr first))
-	      (if (and (pair? (cdr first))
-		       (member (cadr first) terms))
-		  (if (null? (cddr first))
-		      (begin
-			(add-rule-precedence! ruleno (pos-in-list (cadr first) terms))
-			(loop rest))
-		      (lalr-error "prec: directive should be at end of rule: " rhs))
-		  (lalr-error "Invalid prec: directive: " first)))
-	     (else
-	      (lalr-error "Invalid terminal or nonterminal: " first)))))))
-	
-
-  (if (not (pair? (cdr nonterm-def)))
-      (lalr-error "At least one production needed for nonterminal" (car nonterm-def))
-      (let ((name (symbol->string (car nonterm-def))))
-	(let loop1 ((lst (cdr nonterm-def))
-		    (i 1)
-		    (rev-productions-and-actions '()))
-	  (if (not (pair? lst))
-	      (reverse rev-productions-and-actions)
-	      (let* ((rhs  (process-prec-directive (car lst) (+ ruleno i -1)))
-		     (rest (cdr lst))
-		     (prod (map encode (cons (car nonterm-def) rhs))))
-		(for-each (lambda (x)
-			    (if (not (or (member x terms) (member x nonterms)))
-				(lalr-error "Invalid terminal or nonterminal" x)))
-			  rhs)
-		(if (and (pair? rest)
-			 (eq? (car rest) *arrow*)
-			 (pair? (cdr rest)))
-		    (loop1 (cddr rest)
-			   (+ i 1)
-			   (cons (cons prod (cadr rest)) 
-				 rev-productions-and-actions))
-		    (let* ((rhs-length (length rhs))
-			   (action
-			    (cons 'vector
-				 (cons (list 'quote (string->symbol
-						     (string-append
-						      name
-						      "-"
-						      (number->string i))))
-				       (let loop-j ((j 1))
-					 (if (> j rhs-length)
-					     '()
-					     (cons (string->symbol
-						    (string-append
-						     "$"
-						     (number->string j)))
-						   (loop-j (+ j 1)))))))))
-		      (loop1 rest
-			     (+ i 1)
-			     (cons (cons prod action) 
-				   rev-productions-and-actions))))))))))
-
-(define (valid-nonterminal? x)
-  (symbol? x))
-
-(define (valid-terminal? x)
-  (symbol? x))              ; DB 
-
-;; ---------------------------------------------------------------------- ;;
-;; Miscellaneous                                                          ;;
-;; ---------------------------------------------------------------------- ;;
-(define (pos-in-list x lst)
-  (let loop ((lst lst) (i 0))
-    (cond ((not (pair? lst))    #f)
-	  ((equal? (car lst) x) i)
-	  (else                 (loop (cdr lst) (+ i 1))))))
-
-(define (sunion lst1 lst2)		; union of sorted lists
-  (let loop ((L1 lst1)
-	     (L2 lst2))
-    (cond ((null? L1)    L2)
-	  ((null? L2)    L1)
-	  (else 
-	   (let ((x (car L1)) (y (car L2)))
-	     (cond
-	      ((> x y)
-	       (cons y (loop L1 (cdr L2))))
-	      ((< x y)
-	       (cons x (loop (cdr L1) L2)))
-	      (else
-	       (loop (cdr L1) L2))
-	      ))))))
-
-(define (sinsert elem lst)
-  (let loop ((l1 lst))
-    (if (null? l1) 
-	(cons elem l1)
-	(let ((x (car l1)))
-	  (cond ((< elem x)
-		 (cons elem l1))
-		((> elem x)
-		 (cons x (loop (cdr l1))))
-		(else 
-		 l1))))))
-
-(define (lalr-filter p lst)
-  (let loop ((l lst))
-    (if (null? l)
-	'()
-	(let ((x (car l)) (y (cdr l)))
-	(if (p x)
-	    (cons x (loop y))
-	    (loop y))))))
-
-;; ---------------------------------------------------------------------- ;;
-;; Debugging tools ...                                                    ;;
-;; ---------------------------------------------------------------------- ;;
-(define the-terminals #f)		; names of terminal symbols
-(define the-nonterminals #f)		; non-terminals
-
-(define (print-item item-no)
-  (let loop ((i item-no))
-    (let ((v (vector-ref ritem i)))
-      (if (>= v 0)
-	  (loop (+ i 1))
-	  (let* ((rlno    (- v))
-		 (nt      (vector-ref rlhs rlno)))
-	    (display (vector-ref the-nonterminals nt)) (display " --> ")
-	    (let loop ((i (vector-ref rrhs rlno)))
-	      (let ((v (vector-ref ritem i)))
-		(if (= i item-no)
-		    (display ". "))
-		(if (>= v 0)
-		    (begin
-		      (print-symbol v)
-		      (display " ")
-		      (loop (+ i 1)))
-		    (begin 
-		      (display "   (rule ")
-		      (display (- v))
-		      (display ")")
-		      (newline))))))))))
-  
-(define (print-symbol n . port)
-  (display (if (>= n nvars)
-	       (vector-ref the-terminals (- n nvars))
-	       (vector-ref the-nonterminals n))
-           (if (null? port)
-               (current-output-port)
-               (car port))))
-  
-(define (print-states)
-"Print the states of a generated parser."
-  (define (print-action act)
-    (cond
-     ((eq? act '*error*)
-      (display " : Error"))
-     ((eq? act 'accept)
-      (display " : Accept input"))
-     ((< act 0)
-      (display " : reduce using rule ")
-      (display (- act)))
-     (else
-      (display " : shift and goto state ")
-      (display act)))
-    (newline)
-    #t)
-  
-  (define (print-actions acts)
-    (let loop ((l acts))
-      (if (null? l)
-	  #t
-	  (let ((sym (caar l))
-		(act (cdar l)))
-	    (display "   ")
-	    (cond
-	     ((eq? sym 'default)
-	      (display "default action"))
-	     (else
-	      (if (number? sym)
-		  (print-symbol (+ sym nvars))
-		  (display sym))))
-	    (print-action act)
-	    (loop (cdr l))))))
-  
-  (if (not action-table)
-      (begin
-	(display "No generated parser available!")
-	(newline)
-	#f)
-      (begin
-	(display "State table") (newline)
-	(display "-----------") (newline) (newline)
-  
-	(let loop ((l first-state))
-	  (if (null? l)
-	      #t
-	      (let* ((core  (car l))
-		     (i     (core-number core))
-		     (items (core-items core))
-		     (actions (vector-ref action-table i)))
-		(display "state ") (display i) (newline)
-		(newline)
-		(for-each (lambda (x) (display "   ") (print-item x))
-			  items)
-		(newline)
-		(print-actions actions)
-		(newline)
-		(loop (cdr l))))))))
-
-
-	  
-;; ---------------------------------------------------------------------- ;;
-
-(define build-goto-table
-  (lambda ()
-    `(vector
-      ,@(map
-	 (lambda (shifts)
-	   (list 'quote
-		 (if shifts
-		     (let loop ((l (shift-shifts shifts)))
-		       (if (null? l)
-			   '()
-			   (let* ((state  (car l))
-				  (symbol (vector-ref acces-symbol state)))
-			     (if (< symbol nvars)
-				 (cons `(,symbol . ,state)
-				       (loop (cdr l)))
-				 (loop (cdr l))))))
-		     '())))
-	 (vector->list shift-table)))))
-
-
-(define build-reduction-table
-  (lambda (gram/actions)
-    `(vector
-      '()
-      ,@(map
-	 (lambda (p)
-	   (let ((act (cdr p)))
-	     `(lambda (___stack ___sp ___goto-table ___k)
-		,(let* ((nt (caar p)) (rhs (cdar p)) (n (length rhs)))
-		   `(let* (,@(if act
-				 (let loop ((i 1) (l rhs))
-				   (if (pair? l)
-				       (let ((rest (cdr l)))
-					 (cons 
-					  `(,(string->symbol
-					      (string-append
-					       "$"
-					       (number->string 
-						(+ (- n i) 1))))
-					    (vector-ref ___stack (- ___sp ,(- (* i 2) 1))))
-					  (loop (+ i 1) rest)))
-				       '()))
-				 '()))
-		      ,(if (= nt 0)
-			   '$1
-			   `(___push ___stack (- ___sp ,(* 2 n)) 
-				  ,nt ___goto-table ,(cdr p) ___k)))))))
-
-	 gram/actions))))
-	 
-
-;; @section (api "API")                                                   
-
-(define-macro (lalr-parser tokens . rules)
-  (let* ((gram/actions (gen-tables! tokens rules))
-	 (code
-	  `(letrec ((___max-stack-size 500)
-
-		    (___atable         ',action-table)
-		    (___gtable         ,(build-goto-table))
-		    (___grow-stack     (lambda (stack)
-					 ;; make a new stack twice as big as the original
-					 (let ((new-stack (make-vector (* 2 (vector-length stack)) #f)))
-					   ;; then copy the elements...
-					   (let loop ((i (- (vector-length stack) 1)))
-					     (if (< i 0)
-						 new-stack
-						 (begin
-						   (vector-set! new-stack i (vector-ref stack i))
-						   (loop (- i 1))))))))
-	      
-		    (___push           (lambda (stack sp new-cat goto-table lval k)
-					 (let* ((state     (vector-ref stack sp))
-						(new-state (cdr (assq new-cat (vector-ref goto-table state))))
-						(new-sp    (+ sp 2))
-						(stack     (if (< new-sp (vector-length stack))
-							       stack
-							       (___grow-stack stack))))
-					   (vector-set! stack new-sp new-state)
-					   (vector-set! stack (- new-sp 1) lval)
-					   (k stack new-sp))))
-
-		    (___action         (lambda (x l)
-					 (let ((y (assq x l)))
-					   (if y (cdr y) (cdar l)))))
-	      
-		    (___rtable         ,(build-reduction-table gram/actions)))
-
-	     (lambda (lexerp errorp)
-
-	       (let ((stack (make-vector ___max-stack-size 0)))
-		 (let loop ((stack stack) (sp 0) (input (lexerp)))
-		   (let* ((state (vector-ref stack sp))
-			  (i     (if (pair? input) (car input) input))
-			  (attr  (if (pair? input) (cdr input) #f))
-			  (act   (___action i (vector-ref ___atable state))))
-
-		     (if (not (symbol? i))
-			 (errorp "PARSE ERROR: invalid token: " input))
-		 
-		     (cond
-		  
-		      ;; Input succesfully parsed
-		      ((eq? act 'accept)
-		       (vector-ref stack 1))
-		  
-		      ;; Syntax error in input
-		      ((eq? act '*error*)
-		       (if (eq? i '*eoi*)
-			   (errorp "PARSE ERROR : unexpected end of input ")
-			   (errorp "PARSE ERROR : unexpected token : " input)))
-		  
-		      ;; Shift current token on top of the stack
-		      ((>= act 0)
-		       (let ((stack (if (< (+ sp 2) (vector-length stack))
-					stack
-					(___grow-stack stack))))
-			 (vector-set! stack (+ sp 1) attr)
-			 (vector-set! stack (+ sp 2) act)
-			 (loop stack (+ sp 2) (lexerp))))
-
-		      ;; Reduce by rule (- act)
-		      (else 
-		       ((vector-ref ___rtable (- act))
-			stack sp ___gtable
-			(lambda (stack sp)
-			  (loop stack sp input))))))))))))
-    code))
-
-;; arch-tag: 4FE771DE-F56D-11D8-8B77-000A95B4C7DC
diff --git a/module/language/ecmascript/parse.scm b/module/language/ecmascript/parse.scm
index ce731a736..e9d6673ce 100644
--- a/module/language/ecmascript/parse.scm
+++ b/module/language/ecmascript/parse.scm
@@ -1,6 +1,6 @@
 ;;; ECMAScript for Guile
 
-;; Copyright (C) 2009 Free Software Foundation, Inc.
+;; Copyright (C) 2009, 2010 Free Software Foundation, Inc.
 
 ;;;; This library is free software; you can redistribute it and/or
 ;;;; modify it under the terms of the GNU Lesser General Public
@@ -19,23 +19,29 @@
 ;;; Code:
 
 (define-module (language ecmascript parse)
-  #:use-module (language ecmascript parse-lalr)
+  #:use-module (system base lalr)
   #:use-module (language ecmascript tokenize)
-  #:export (read-ecmascript read-ecmascript/1 parse-ecmascript))
+  #:export (read-ecmascript read-ecmascript/1 make-parser))
 
 (define (syntax-error message . args)
   (apply throw 'SyntaxError message args))
 
 (define (read-ecmascript port)
-  (parse-ecmascript (make-tokenizer port) syntax-error))
+  (let ((parse (make-parser)))
+    (parse (make-tokenizer port) syntax-error)))
 
 (define (read-ecmascript/1 port)
-  (parse-ecmascript (make-tokenizer/1 port) syntax-error))
+  (let ((parse (make-parser)))
+    (parse (make-tokenizer/1 port) syntax-error)))
 
 (define *eof-object*
   (call-with-input-string "" read-char))
 
-(define parse-ecmascript
+(define (make-parser)
+  ;; Return a fresh ECMAScript parser.  Parsers produced by `lalr-scm' are now
+  ;; stateful (e.g., they won't invoke the tokenizer any more once it has
+  ;; returned `*eoi*'), hence the need to instantiate new parsers.
+
   (lalr-parser
    ;; terminal (i.e. input) token types
    (lbrace rbrace lparen rparen lbracket rbracket dot semicolon comma <
@@ -49,289 +55,289 @@
     Identifier StringLiteral NumericLiteral RegexpLiteral)
 
 
-   (Program (SourceElements) -> $1
-            (*eoi*) -> *eof-object*)
+   (Program (SourceElements) : $1
+            (*eoi*) : *eof-object*)
 
    ;;
    ;; Verily, here we define statements. Expressions are defined
    ;; afterwards.
    ;;
 
-   (SourceElement (Statement) -> $1
-                  (FunctionDeclaration) -> $1)
+   (SourceElement (Statement) : $1
+                  (FunctionDeclaration) : $1)
 
-   (FunctionDeclaration (function Identifier lparen rparen lbrace FunctionBody rbrace) -> `(var (,$2 (lambda () ,$6)))
-                        (function Identifier lparen FormalParameterList rparen lbrace FunctionBody rbrace) -> `(var (,$2 (lambda ,$4 ,$7))))
-   (FunctionExpression (function lparen rparen lbrace FunctionBody rbrace) -> `(lambda () ,$5)
-                       (function Identifier lparen rparen lbrace FunctionBody rbrace) -> `(lambda () ,$6)
-                       (function lparen FormalParameterList rparen lbrace FunctionBody rbrace) -> `(lambda ,$3 ,$6)
-                       (function Identifier lparen FormalParameterList rparen lbrace FunctionBody rbrace) -> `(lambda ,$4 ,$7))
-   (FormalParameterList (Identifier) -> `(,$1)
-                        (FormalParameterList comma Identifier) -> `(,@$1 ,$3))
-   (SourceElements (SourceElement) -> $1
-                   (SourceElements SourceElement) -> (if (and (pair? $1) (eq? (car $1) 'begin))
+   (FunctionDeclaration (function Identifier lparen rparen lbrace FunctionBody rbrace) : `(var (,$2 (lambda () ,$6)))
+                        (function Identifier lparen FormalParameterList rparen lbrace FunctionBody rbrace) : `(var (,$2 (lambda ,$4 ,$7))))
+   (FunctionExpression (function lparen rparen lbrace FunctionBody rbrace) : `(lambda () ,$5)
+                       (function Identifier lparen rparen lbrace FunctionBody rbrace) : `(lambda () ,$6)
+                       (function lparen FormalParameterList rparen lbrace FunctionBody rbrace) : `(lambda ,$3 ,$6)
+                       (function Identifier lparen FormalParameterList rparen lbrace FunctionBody rbrace) : `(lambda ,$4 ,$7))
+   (FormalParameterList (Identifier) : `(,$1)
+                        (FormalParameterList comma Identifier) : `(,@$1 ,$3))
+   (SourceElements (SourceElement) : $1
+                   (SourceElements SourceElement) : (if (and (pair? $1) (eq? (car $1) 'begin))
                                                          `(begin ,@(cdr $1) ,$2)
                                                          `(begin ,$1 ,$2)))
-   (FunctionBody (SourceElements) -> $1)
+   (FunctionBody (SourceElements) : $1)
 
-   (Statement (Block) -> $1
-              (VariableStatement) -> $1
-              (EmptyStatement) -> $1
-              (ExpressionStatement) -> $1
-              (IfStatement) -> $1
-              (IterationStatement) -> $1
-              (ContinueStatement) -> $1
-              (BreakStatement) -> $1
-              (ReturnStatement) -> $1
-              (WithStatement) -> $1
-              (LabelledStatement) -> $1
-              (SwitchStatement) -> $1
-              (ThrowStatement) -> $1
-              (TryStatement) -> $1)
+   (Statement (Block) : $1
+              (VariableStatement) : $1
+              (EmptyStatement) : $1
+              (ExpressionStatement) : $1
+              (IfStatement) : $1
+              (IterationStatement) : $1
+              (ContinueStatement) : $1
+              (BreakStatement) : $1
+              (ReturnStatement) : $1
+              (WithStatement) : $1
+              (LabelledStatement) : $1
+              (SwitchStatement) : $1
+              (ThrowStatement) : $1
+              (TryStatement) : $1)
 
-   (Block (lbrace StatementList rbrace) -> `(block ,$2))
-   (StatementList (Statement) -> $1
-                  (StatementList Statement) -> (if (and (pair? $1) (eq? (car $1) 'begin))
+   (Block (lbrace StatementList rbrace) : `(block ,$2))
+   (StatementList (Statement) : $1
+                  (StatementList Statement) : (if (and (pair? $1) (eq? (car $1) 'begin))
                                                    `(begin ,@(cdr $1) ,$2)
                                                    `(begin ,$1 ,$2)))
 
-   (VariableStatement (var VariableDeclarationList) -> `(var ,@$2))
-   (VariableDeclarationList (VariableDeclaration) -> `(,$1)
-                            (VariableDeclarationList comma VariableDeclaration) -> `(,@$1 ,$2))
-   (VariableDeclarationListNoIn (VariableDeclarationNoIn) -> `(,$1)
-                                (VariableDeclarationListNoIn comma VariableDeclarationNoIn) -> `(,@$1 ,$2))
-   (VariableDeclaration (Identifier) -> `(,$1)
-                        (Identifier Initialiser) -> `(,$1 ,$2))
-   (VariableDeclarationNoIn (Identifier) -> `(,$1)
-                            (Identifier Initialiser) -> `(,$1 ,$2))
-   (Initialiser (= AssignmentExpression) -> $2)
-   (InitialiserNoIn (= AssignmentExpressionNoIn) -> $2)
+   (VariableStatement (var VariableDeclarationList) : `(var ,@$2))
+   (VariableDeclarationList (VariableDeclaration) : `(,$1)
+                            (VariableDeclarationList comma VariableDeclaration) : `(,@$1 ,$2))
+   (VariableDeclarationListNoIn (VariableDeclarationNoIn) : `(,$1)
+                                (VariableDeclarationListNoIn comma VariableDeclarationNoIn) : `(,@$1 ,$2))
+   (VariableDeclaration (Identifier) : `(,$1)
+                        (Identifier Initialiser) : `(,$1 ,$2))
+   (VariableDeclarationNoIn (Identifier) : `(,$1)
+                            (Identifier Initialiser) : `(,$1 ,$2))
+   (Initialiser (= AssignmentExpression) : $2)
+   (InitialiserNoIn (= AssignmentExpressionNoIn) : $2)
 
-   (EmptyStatement (semicolon) -> '(begin))
+   (EmptyStatement (semicolon) : '(begin))
 
-   (ExpressionStatement (Expression semicolon) -> $1)
+   (ExpressionStatement (Expression semicolon) : $1)
 
-   (IfStatement (if lparen Expression rparen Statement else Statement) -> `(if ,$3 ,$5 ,$7)
-                (if lparen Expression rparen Statement) -> `(if ,$3 ,$5))
+   (IfStatement (if lparen Expression rparen Statement else Statement) : `(if ,$3 ,$5 ,$7)
+                (if lparen Expression rparen Statement) : `(if ,$3 ,$5))
    
-   (IterationStatement (do Statement while lparen Expression rparen semicolon) -> `(do ,$2 ,$5)
+   (IterationStatement (do Statement while lparen Expression rparen semicolon) : `(do ,$2 ,$5)
 
-                       (while lparen Expression rparen Statement) -> `(while ,$3 ,$5)
+                       (while lparen Expression rparen Statement) : `(while ,$3 ,$5)
 
-                       (for lparen semicolon semicolon rparen Statement) -> `(for #f #f #f ,$6)
-                       (for lparen semicolon semicolon Expression rparen Statement) -> `(for #f #f ,$5 ,$7)
-                       (for lparen semicolon Expression semicolon rparen Statement) -> `(for #f ,$4 #f ,$7)
-                       (for lparen semicolon Expression semicolon Expression rparen Statement) -> `(for #f ,$4 ,$6 ,$8)
+                       (for lparen semicolon semicolon rparen Statement) : `(for #f #f #f ,$6)
+                       (for lparen semicolon semicolon Expression rparen Statement) : `(for #f #f ,$5 ,$7)
+                       (for lparen semicolon Expression semicolon rparen Statement) : `(for #f ,$4 #f ,$7)
+                       (for lparen semicolon Expression semicolon Expression rparen Statement) : `(for #f ,$4 ,$6 ,$8)
 
-                       (for lparen ExpressionNoIn semicolon semicolon rparen Statement) -> `(for ,$3 #f #f ,$7)
-                       (for lparen ExpressionNoIn semicolon semicolon Expression rparen Statement) -> `(for ,$3 #f ,$6 ,$8)
-                       (for lparen ExpressionNoIn semicolon Expression semicolon rparen Statement) -> `(for ,$3 ,$5 #f ,$8)
-                       (for lparen ExpressionNoIn semicolon Expression semicolon Expression rparen Statement) -> `(for ,$3 ,$5 ,$7 ,$9)
+                       (for lparen ExpressionNoIn semicolon semicolon rparen Statement) : `(for ,$3 #f #f ,$7)
+                       (for lparen ExpressionNoIn semicolon semicolon Expression rparen Statement) : `(for ,$3 #f ,$6 ,$8)
+                       (for lparen ExpressionNoIn semicolon Expression semicolon rparen Statement) : `(for ,$3 ,$5 #f ,$8)
+                       (for lparen ExpressionNoIn semicolon Expression semicolon Expression rparen Statement) : `(for ,$3 ,$5 ,$7 ,$9)
 
-                       (for lparen var VariableDeclarationListNoIn semicolon semicolon rparen Statement) -> `(for (var ,@$4) #f #f ,$8)
-                       (for lparen var VariableDeclarationListNoIn semicolon semicolon Expression rparen Statement) -> `(for (var ,@$4) #f ,$7 ,$9)
-                       (for lparen var VariableDeclarationListNoIn semicolon Expression semicolon rparen Statement) -> `(for (var ,@$4) ,$6 #f ,$9)
-                       (for lparen var VariableDeclarationListNoIn semicolon Expression semicolon Expression rparen Statement) -> `(for (var ,@$4) ,$6 ,$8 ,$10)
+                       (for lparen var VariableDeclarationListNoIn semicolon semicolon rparen Statement) : `(for (var ,@$4) #f #f ,$8)
+                       (for lparen var VariableDeclarationListNoIn semicolon semicolon Expression rparen Statement) : `(for (var ,@$4) #f ,$7 ,$9)
+                       (for lparen var VariableDeclarationListNoIn semicolon Expression semicolon rparen Statement) : `(for (var ,@$4) ,$6 #f ,$9)
+                       (for lparen var VariableDeclarationListNoIn semicolon Expression semicolon Expression rparen Statement) : `(for (var ,@$4) ,$6 ,$8 ,$10)
 
-                       (for lparen LeftHandSideExpression in Expression rparen Statement) -> `(for-in ,$3 ,$5 ,$7)
-                       (for lparen var VariableDeclarationNoIn in Expression rparen Statement) -> `(begin (var ,$4) (for-in (ref ,@$4) ,$6 ,$8)))
+                       (for lparen LeftHandSideExpression in Expression rparen Statement) : `(for-in ,$3 ,$5 ,$7)
+                       (for lparen var VariableDeclarationNoIn in Expression rparen Statement) : `(begin (var ,$4) (for-in (ref ,@$4) ,$6 ,$8)))
 
-   (ContinueStatement (continue Identifier semicolon) -> `(continue ,$2)
-                      (continue semicolon) -> `(continue))
+   (ContinueStatement (continue Identifier semicolon) : `(continue ,$2)
+                      (continue semicolon) : `(continue))
 
-   (BreakStatement (break Identifier semicolon) -> `(break ,$2)
-                   (break semicolon) -> `(break))
+   (BreakStatement (break Identifier semicolon) : `(break ,$2)
+                   (break semicolon) : `(break))
 
-   (ReturnStatement (return Expression semicolon) -> `(return ,$2)
-                    (return semicolon) -> `(return))
+   (ReturnStatement (return Expression semicolon) : `(return ,$2)
+                    (return semicolon) : `(return))
 
-   (WithStatement (with lparen Expression rparen Statement) -> `(with ,$3 ,$5))
+   (WithStatement (with lparen Expression rparen Statement) : `(with ,$3 ,$5))
 
-   (SwitchStatement (switch lparen Expression rparen CaseBlock) -> `(switch ,$3 ,@$5))
-   (CaseBlock (lbrace rbrace) -> '()
-              (lbrace CaseClauses rbrace) -> $2
-              (lbrace CaseClauses DefaultClause rbrace) -> `(,@$2 ,@$3)
-              (lbrace DefaultClause rbrace) -> `(,$2)
-              (lbrace DefaultClause CaseClauses rbrace) -> `(,@$2 ,@$3))
-   (CaseClauses (CaseClause) -> `(,$1)
-                (CaseClauses CaseClause) -> `(,@$1 ,$2))
-   (CaseClause (case Expression colon) -> `(case ,$2)
-               (case Expression colon StatementList) -> `(case ,$2 ,$4))
-   (DefaultClause (default colon) -> `(default)
-                  (default colon StatementList) -> `(default ,$3))
+   (SwitchStatement (switch lparen Expression rparen CaseBlock) : `(switch ,$3 ,@$5))
+   (CaseBlock (lbrace rbrace) : '()
+              (lbrace CaseClauses rbrace) : $2
+              (lbrace CaseClauses DefaultClause rbrace) : `(,@$2 ,@$3)
+              (lbrace DefaultClause rbrace) : `(,$2)
+              (lbrace DefaultClause CaseClauses rbrace) : `(,@$2 ,@$3))
+   (CaseClauses (CaseClause) : `(,$1)
+                (CaseClauses CaseClause) : `(,@$1 ,$2))
+   (CaseClause (case Expression colon) : `(case ,$2)
+               (case Expression colon StatementList) : `(case ,$2 ,$4))
+   (DefaultClause (default colon) : `(default)
+                  (default colon StatementList) : `(default ,$3))
 
-   (LabelledStatement (Identifier colon Statement) -> `(label ,$1 ,$3))
+   (LabelledStatement (Identifier colon Statement) : `(label ,$1 ,$3))
 
-   (ThrowStatement (throw Expression semicolon) -> `(throw ,$2))
+   (ThrowStatement (throw Expression semicolon) : `(throw ,$2))
 
-   (TryStatement (try Block Catch) -> `(try ,$2 ,$3 #f)
-                 (try Block Finally) -> `(try ,$2 #f ,$3)
-                 (try Block Catch Finally) -> `(try ,$2 ,$3 ,$4))
-   (Catch (catch lparen Identifier rparen Block) -> `(catch ,$3 ,$5))
-   (Finally (finally Block) -> `(finally ,$2))
+   (TryStatement (try Block Catch) : `(try ,$2 ,$3 #f)
+                 (try Block Finally) : `(try ,$2 #f ,$3)
+                 (try Block Catch Finally) : `(try ,$2 ,$3 ,$4))
+   (Catch (catch lparen Identifier rparen Block) : `(catch ,$3 ,$5))
+   (Finally (finally Block) : `(finally ,$2))
 
    ;;
    ;; As promised, expressions. We build up to Expression bottom-up, so
    ;; as to get operator precedence right.
    ;;
 
-   (PrimaryExpression (this) -> 'this
-                      (null) -> 'null
-                      (true) -> 'true
-                      (false) -> 'false
-                      (Identifier) -> `(ref ,$1)
-                      (StringLiteral) -> `(string ,$1)
-                      (RegexpLiteral) -> `(regexp ,$1)
-                      (NumericLiteral) -> `(number ,$1)
-                      (ArrayLiteral) -> $1
-                      (ObjectLiteral) -> $1
-                      (lparen Expression rparen) -> $2)
+   (PrimaryExpression (this) : 'this
+                      (null) : 'null
+                      (true) : 'true
+                      (false) : 'false
+                      (Identifier) : `(ref ,$1)
+                      (StringLiteral) : `(string ,$1)
+                      (RegexpLiteral) : `(regexp ,$1)
+                      (NumericLiteral) : `(number ,$1)
+                      (ArrayLiteral) : $1
+                      (ObjectLiteral) : $1
+                      (lparen Expression rparen) : $2)
 
-   (ArrayLiteral (lbracket rbracket) -> '(array)
-                 (lbracket Elision rbracket) -> '(array ,@$2)
-                 (lbracket ElementList rbracket) -> `(array ,@$2)
-                 (lbracket ElementList comma rbracket) -> `(array ,@$2)
-                 (lbracket ElementList comma Elision rbracket) -> `(array ,@$2))
-   (ElementList (AssignmentExpression) -> `(,$1)
-                (Elision AssignmentExpression) -> `(,@$1 ,$2)
-                (ElementList comma AssignmentExpression) -> `(,@$1 ,$3)
-                (ElementList comma Elision AssignmentExpression) -> `(,@$1 ,@$3 ,$4))
-   (Elision (comma) -> '((number 0))
-            (Elision comma) -> `(,@$1 (number 0)))
+   (ArrayLiteral (lbracket rbracket) : '(array)
+                 (lbracket Elision rbracket) : '(array ,@$2)
+                 (lbracket ElementList rbracket) : `(array ,@$2)
+                 (lbracket ElementList comma rbracket) : `(array ,@$2)
+                 (lbracket ElementList comma Elision rbracket) : `(array ,@$2))
+   (ElementList (AssignmentExpression) : `(,$1)
+                (Elision AssignmentExpression) : `(,@$1 ,$2)
+                (ElementList comma AssignmentExpression) : `(,@$1 ,$3)
+                (ElementList comma Elision AssignmentExpression) : `(,@$1 ,@$3 ,$4))
+   (Elision (comma) : '((number 0))
+            (Elision comma) : `(,@$1 (number 0)))
 
-   (ObjectLiteral (lbrace rbrace) -> `(object)
-                  (lbrace PropertyNameAndValueList rbrace) -> `(object ,@$2))
-   (PropertyNameAndValueList (PropertyName colon AssignmentExpression) -> `((,$1 ,$3))
-                             (PropertyNameAndValueList comma PropertyName colon AssignmentExpression) -> `(,@$1 (,$3 ,$5)))
-   (PropertyName (Identifier) -> $1
-                 (StringLiteral) -> (string->symbol $1)
-                 (NumericLiteral) -> $1)
+   (ObjectLiteral (lbrace rbrace) : `(object)
+                  (lbrace PropertyNameAndValueList rbrace) : `(object ,@$2))
+   (PropertyNameAndValueList (PropertyName colon AssignmentExpression) : `((,$1 ,$3))
+                             (PropertyNameAndValueList comma PropertyName colon AssignmentExpression) : `(,@$1 (,$3 ,$5)))
+   (PropertyName (Identifier) : $1
+                 (StringLiteral) : (string->symbol $1)
+                 (NumericLiteral) : $1)
 
-   (MemberExpression (PrimaryExpression) -> $1
-                     (FunctionExpression) -> $1
-                     (MemberExpression lbracket Expression rbracket) -> `(aref ,$1 ,$3)
-                     (MemberExpression dot Identifier) -> `(pref ,$1 ,$3)
-                     (new MemberExpression Arguments) -> `(new ,$2 ,$3))
+   (MemberExpression (PrimaryExpression) : $1
+                     (FunctionExpression) : $1
+                     (MemberExpression lbracket Expression rbracket) : `(aref ,$1 ,$3)
+                     (MemberExpression dot Identifier) : `(pref ,$1 ,$3)
+                     (new MemberExpression Arguments) : `(new ,$2 ,$3))
 
-   (NewExpression (MemberExpression) -> $1
-                  (new NewExpression) -> `(new ,$2 ()))
+   (NewExpression (MemberExpression) : $1
+                  (new NewExpression) : `(new ,$2 ()))
 
-   (CallExpression (MemberExpression Arguments) -> `(call ,$1 ,$2)
-                   (CallExpression Arguments) -> `(call ,$1 ,$2)
-                   (CallExpression lbracket Expression rbracket) -> `(aref ,$1 ,$3)
-                   (CallExpression dot Identifier) -> `(pref ,$1 ,$3))
-   (Arguments (lparen rparen) -> '()
-              (lparen ArgumentList rparen) -> $2)
-   (ArgumentList (AssignmentExpression) -> `(,$1)
-                 (ArgumentList comma AssignmentExpression) -> `(,@$1 ,$3))
+   (CallExpression (MemberExpression Arguments) : `(call ,$1 ,$2)
+                   (CallExpression Arguments) : `(call ,$1 ,$2)
+                   (CallExpression lbracket Expression rbracket) : `(aref ,$1 ,$3)
+                   (CallExpression dot Identifier) : `(pref ,$1 ,$3))
+   (Arguments (lparen rparen) : '()
+              (lparen ArgumentList rparen) : $2)
+   (ArgumentList (AssignmentExpression) : `(,$1)
+                 (ArgumentList comma AssignmentExpression) : `(,@$1 ,$3))
 
-   (LeftHandSideExpression (NewExpression) -> $1
-                           (CallExpression) -> $1)
+   (LeftHandSideExpression (NewExpression) : $1
+                           (CallExpression) : $1)
 
-   (PostfixExpression (LeftHandSideExpression) -> $1
-                      (LeftHandSideExpression ++) -> `(postinc ,$1)
-                      (LeftHandSideExpression --) -> `(postdec ,$1))
+   (PostfixExpression (LeftHandSideExpression) : $1
+                      (LeftHandSideExpression ++) : `(postinc ,$1)
+                      (LeftHandSideExpression --) : `(postdec ,$1))
 
-   (UnaryExpression (PostfixExpression) -> $1
-                    (delete UnaryExpression) -> `(delete ,$2)
-                    (void UnaryExpression) -> `(void ,$2)
-                    (typeof UnaryExpression) -> `(typeof ,$2)
-                    (++ UnaryExpression) -> `(preinc ,$2)
-                    (-- UnaryExpression) -> `(predec ,$2)
-                    (+ UnaryExpression) -> `(+ ,$2)
-                    (- UnaryExpression) -> `(- ,$2)
-                    (~ UnaryExpression) -> `(~ ,$2)
-                    (! UnaryExpression) -> `(! ,$2))
+   (UnaryExpression (PostfixExpression) : $1
+                    (delete UnaryExpression) : `(delete ,$2)
+                    (void UnaryExpression) : `(void ,$2)
+                    (typeof UnaryExpression) : `(typeof ,$2)
+                    (++ UnaryExpression) : `(preinc ,$2)
+                    (-- UnaryExpression) : `(predec ,$2)
+                    (+ UnaryExpression) : `(+ ,$2)
+                    (- UnaryExpression) : `(- ,$2)
+                    (~ UnaryExpression) : `(~ ,$2)
+                    (! UnaryExpression) : `(! ,$2))
 
-   (MultiplicativeExpression (UnaryExpression) -> $1
-                             (MultiplicativeExpression * UnaryExpression) -> `(* ,$1 ,$3)
-                             (MultiplicativeExpression / UnaryExpression) -> `(/ ,$1 ,$3)
-                             (MultiplicativeExpression % UnaryExpression) -> `(% ,$1 ,$3))
+   (MultiplicativeExpression (UnaryExpression) : $1
+                             (MultiplicativeExpression * UnaryExpression) : `(* ,$1 ,$3)
+                             (MultiplicativeExpression / UnaryExpression) : `(/ ,$1 ,$3)
+                             (MultiplicativeExpression % UnaryExpression) : `(% ,$1 ,$3))
 
-   (AdditiveExpression (MultiplicativeExpression) -> $1
-                       (AdditiveExpression + MultiplicativeExpression) -> `(+ ,$1 ,$3)
-                       (AdditiveExpression - MultiplicativeExpression) -> `(- ,$1 ,$3))
+   (AdditiveExpression (MultiplicativeExpression) : $1
+                       (AdditiveExpression + MultiplicativeExpression) : `(+ ,$1 ,$3)
+                       (AdditiveExpression - MultiplicativeExpression) : `(- ,$1 ,$3))
 
-   (ShiftExpression (AdditiveExpression) -> $1
-                    (ShiftExpression << MultiplicativeExpression) -> `(<< ,$1 ,$3)
-                    (ShiftExpression >> MultiplicativeExpression) -> `(>> ,$1 ,$3)
-                    (ShiftExpression >>> MultiplicativeExpression) -> `(>>> ,$1 ,$3))
+   (ShiftExpression (AdditiveExpression) : $1
+                    (ShiftExpression << MultiplicativeExpression) : `(<< ,$1 ,$3)
+                    (ShiftExpression >> MultiplicativeExpression) : `(>> ,$1 ,$3)
+                    (ShiftExpression >>> MultiplicativeExpression) : `(>>> ,$1 ,$3))
 
-   (RelationalExpression (ShiftExpression) -> $1
-                         (RelationalExpression < ShiftExpression) -> `(< ,$1 ,$3)
-                         (RelationalExpression > ShiftExpression) -> `(> ,$1 ,$3)
-                         (RelationalExpression <= ShiftExpression) -> `(<= ,$1 ,$3)
-                         (RelationalExpression >= ShiftExpression) -> `(>= ,$1 ,$3)
-                         (RelationalExpression instanceof ShiftExpression) -> `(instanceof ,$1 ,$3)
-                         (RelationalExpression in ShiftExpression) -> `(in ,$1 ,$3))
+   (RelationalExpression (ShiftExpression) : $1
+                         (RelationalExpression < ShiftExpression) : `(< ,$1 ,$3)
+                         (RelationalExpression > ShiftExpression) : `(> ,$1 ,$3)
+                         (RelationalExpression <= ShiftExpression) : `(<= ,$1 ,$3)
+                         (RelationalExpression >= ShiftExpression) : `(>= ,$1 ,$3)
+                         (RelationalExpression instanceof ShiftExpression) : `(instanceof ,$1 ,$3)
+                         (RelationalExpression in ShiftExpression) : `(in ,$1 ,$3))
 
-   (RelationalExpressionNoIn (ShiftExpression) -> $1
-                             (RelationalExpressionNoIn < ShiftExpression) -> `(< ,$1 ,$3)
-                             (RelationalExpressionNoIn > ShiftExpression) -> `(> ,$1 ,$3)
-                             (RelationalExpressionNoIn <= ShiftExpression) -> `(<= ,$1 ,$3)
-                             (RelationalExpressionNoIn >= ShiftExpression) -> `(>= ,$1 ,$3)
-                             (RelationalExpressionNoIn instanceof ShiftExpression) -> `(instanceof ,$1 ,$3))
+   (RelationalExpressionNoIn (ShiftExpression) : $1
+                             (RelationalExpressionNoIn < ShiftExpression) : `(< ,$1 ,$3)
+                             (RelationalExpressionNoIn > ShiftExpression) : `(> ,$1 ,$3)
+                             (RelationalExpressionNoIn <= ShiftExpression) : `(<= ,$1 ,$3)
+                             (RelationalExpressionNoIn >= ShiftExpression) : `(>= ,$1 ,$3)
+                             (RelationalExpressionNoIn instanceof ShiftExpression) : `(instanceof ,$1 ,$3))
 
-   (EqualityExpression (RelationalExpression) -> $1
-                       (EqualityExpression == RelationalExpression) -> `(== ,$1 ,$3)
-                       (EqualityExpression != RelationalExpression) -> `(!= ,$1 ,$3)
-                       (EqualityExpression === RelationalExpression) -> `(=== ,$1 ,$3)
-                       (EqualityExpression !== RelationalExpression) -> `(!== ,$1 ,$3))
+   (EqualityExpression (RelationalExpression) : $1
+                       (EqualityExpression == RelationalExpression) : `(== ,$1 ,$3)
+                       (EqualityExpression != RelationalExpression) : `(!= ,$1 ,$3)
+                       (EqualityExpression === RelationalExpression) : `(=== ,$1 ,$3)
+                       (EqualityExpression !== RelationalExpression) : `(!== ,$1 ,$3))
 
-   (EqualityExpressionNoIn (RelationalExpressionNoIn) -> $1
-                           (EqualityExpressionNoIn == RelationalExpressionNoIn) -> `(== ,$1 ,$3)
-                           (EqualityExpressionNoIn != RelationalExpressionNoIn) -> `(!= ,$1 ,$3)
-                           (EqualityExpressionNoIn === RelationalExpressionNoIn) -> `(=== ,$1 ,$3)
-                           (EqualityExpressionNoIn !== RelationalExpressionNoIn) -> `(!== ,$1 ,$3))
+   (EqualityExpressionNoIn (RelationalExpressionNoIn) : $1
+                           (EqualityExpressionNoIn == RelationalExpressionNoIn) : `(== ,$1 ,$3)
+                           (EqualityExpressionNoIn != RelationalExpressionNoIn) : `(!= ,$1 ,$3)
+                           (EqualityExpressionNoIn === RelationalExpressionNoIn) : `(=== ,$1 ,$3)
+                           (EqualityExpressionNoIn !== RelationalExpressionNoIn) : `(!== ,$1 ,$3))
 
-   (BitwiseANDExpression (EqualityExpression) -> $1
-                         (BitwiseANDExpression & EqualityExpression) -> `(& ,$1 ,$3))
-   (BitwiseANDExpressionNoIn (EqualityExpressionNoIn) -> $1
-                             (BitwiseANDExpressionNoIn & EqualityExpressionNoIn) -> `(& ,$1 ,$3))
+   (BitwiseANDExpression (EqualityExpression) : $1
+                         (BitwiseANDExpression & EqualityExpression) : `(& ,$1 ,$3))
+   (BitwiseANDExpressionNoIn (EqualityExpressionNoIn) : $1
+                             (BitwiseANDExpressionNoIn & EqualityExpressionNoIn) : `(& ,$1 ,$3))
 
-   (BitwiseXORExpression (BitwiseANDExpression) -> $1
-                         (BitwiseXORExpression ^ BitwiseANDExpression) -> `(^ ,$1 ,$3))
-   (BitwiseXORExpressionNoIn (BitwiseANDExpressionNoIn) -> $1
-                             (BitwiseXORExpressionNoIn ^ BitwiseANDExpressionNoIn) -> `(^ ,$1 ,$3))
+   (BitwiseXORExpression (BitwiseANDExpression) : $1
+                         (BitwiseXORExpression ^ BitwiseANDExpression) : `(^ ,$1 ,$3))
+   (BitwiseXORExpressionNoIn (BitwiseANDExpressionNoIn) : $1
+                             (BitwiseXORExpressionNoIn ^ BitwiseANDExpressionNoIn) : `(^ ,$1 ,$3))
 
-   (BitwiseORExpression (BitwiseXORExpression) -> $1
-                        (BitwiseORExpression bor BitwiseXORExpression) -> `(bor ,$1 ,$3))
-   (BitwiseORExpressionNoIn (BitwiseXORExpressionNoIn) -> $1
-                            (BitwiseORExpressionNoIn bor BitwiseXORExpressionNoIn) -> `(bor ,$1 ,$3))
+   (BitwiseORExpression (BitwiseXORExpression) : $1
+                        (BitwiseORExpression bor BitwiseXORExpression) : `(bor ,$1 ,$3))
+   (BitwiseORExpressionNoIn (BitwiseXORExpressionNoIn) : $1
+                            (BitwiseORExpressionNoIn bor BitwiseXORExpressionNoIn) : `(bor ,$1 ,$3))
 
-   (LogicalANDExpression (BitwiseORExpression) -> $1
-                         (LogicalANDExpression && BitwiseORExpression) -> `(and ,$1 ,$3))
-   (LogicalANDExpressionNoIn (BitwiseORExpressionNoIn) -> $1
-                             (LogicalANDExpressionNoIn && BitwiseORExpressionNoIn) -> `(and ,$1 ,$3))
+   (LogicalANDExpression (BitwiseORExpression) : $1
+                         (LogicalANDExpression && BitwiseORExpression) : `(and ,$1 ,$3))
+   (LogicalANDExpressionNoIn (BitwiseORExpressionNoIn) : $1
+                             (LogicalANDExpressionNoIn && BitwiseORExpressionNoIn) : `(and ,$1 ,$3))
 
-   (LogicalORExpression (LogicalANDExpression) -> $1
-                        (LogicalORExpression or LogicalANDExpression) -> `(or ,$1 ,$3))
-   (LogicalORExpressionNoIn (LogicalANDExpressionNoIn) -> $1
-                            (LogicalORExpressionNoIn or LogicalANDExpressionNoIn) -> `(or ,$1 ,$3))
+   (LogicalORExpression (LogicalANDExpression) : $1
+                        (LogicalORExpression or LogicalANDExpression) : `(or ,$1 ,$3))
+   (LogicalORExpressionNoIn (LogicalANDExpressionNoIn) : $1
+                            (LogicalORExpressionNoIn or LogicalANDExpressionNoIn) : `(or ,$1 ,$3))
 
-   (ConditionalExpression (LogicalORExpression) -> $1
-                          (LogicalORExpression ? AssignmentExpression colon AssignmentExpression) -> `(if ,$1 ,$3 ,$5))
-   (ConditionalExpressionNoIn (LogicalORExpressionNoIn) -> $1
-                              (LogicalORExpressionNoIn ? AssignmentExpressionNoIn colon AssignmentExpressionNoIn) -> `(if ,$1 ,$3 ,$5))
+   (ConditionalExpression (LogicalORExpression) : $1
+                          (LogicalORExpression ? AssignmentExpression colon AssignmentExpression) : `(if ,$1 ,$3 ,$5))
+   (ConditionalExpressionNoIn (LogicalORExpressionNoIn) : $1
+                              (LogicalORExpressionNoIn ? AssignmentExpressionNoIn colon AssignmentExpressionNoIn) : `(if ,$1 ,$3 ,$5))
 
-   (AssignmentExpression (ConditionalExpression) -> $1
-                         (LeftHandSideExpression AssignmentOperator AssignmentExpression) -> `(,$2 ,$1 ,$3))
-   (AssignmentExpressionNoIn (ConditionalExpressionNoIn) -> $1
-                             (LeftHandSideExpression AssignmentOperator AssignmentExpressionNoIn) -> `(,$2 ,$1 ,$3))
-   (AssignmentOperator (=) -> '=
-                       (*=) -> '*=
-                       (/=) -> '/=
-                       (%=) -> '%=
-                       (+=) -> '+=
-                       (-=) -> '-=
-                       (<<=) -> '<<=
-                       (>>=) -> '>>=
-                       (>>>=) -> '>>>=
-                       (&=) -> '&=
-                       (^=) -> '^=
-                       (bor=) -> 'bor=)
+   (AssignmentExpression (ConditionalExpression) : $1
+                         (LeftHandSideExpression AssignmentOperator AssignmentExpression) : `(,$2 ,$1 ,$3))
+   (AssignmentExpressionNoIn (ConditionalExpressionNoIn) : $1
+                             (LeftHandSideExpression AssignmentOperator AssignmentExpressionNoIn) : `(,$2 ,$1 ,$3))
+   (AssignmentOperator (=) : '=
+                       (*=) : '*=
+                       (/=) : '/=
+                       (%=) : '%=
+                       (+=) : '+=
+                       (-=) : '-=
+                       (<<=) : '<<=
+                       (>>=) : '>>=
+                       (>>>=) : '>>>=
+                       (&=) : '&=
+                       (^=) : '^=
+                       (bor=) : 'bor=)
 
-   (Expression (AssignmentExpression) -> $1
-               (Expression comma AssignmentExpression) -> `(begin ,$1 ,$3))
-   (ExpressionNoIn (AssignmentExpressionNoIn) -> $1
-                   (ExpressionNoIn comma AssignmentExpressionNoIn) -> `(begin ,$1 ,$3))))
+   (Expression (AssignmentExpression) : $1
+               (Expression comma AssignmentExpression) : `(begin ,$1 ,$3))
+   (ExpressionNoIn (AssignmentExpressionNoIn) : $1
+                   (ExpressionNoIn comma AssignmentExpressionNoIn) : `(begin ,$1 ,$3))))
diff --git a/module/language/ecmascript/tokenize.scm b/module/language/ecmascript/tokenize.scm
index 2ab8045cc..65a8b1e62 100644
--- a/module/language/ecmascript/tokenize.scm
+++ b/module/language/ecmascript/tokenize.scm
@@ -1,6 +1,6 @@
 ;;; ECMAScript for Guile
 
-;; Copyright (C) 2009 Free Software Foundation, Inc.
+;; Copyright (C) 2009, 2010 Free Software Foundation, Inc.
 
 ;;;; This library is free software; you can redistribute it and/or
 ;;;; modify it under the terms of the GNU Lesser General Public
@@ -21,6 +21,7 @@
 (define-module (language ecmascript tokenize)
   #:use-module (ice-9 rdelim)
   #:use-module ((srfi srfi-1) #:select (unfold-right))
+  #:use-module (system base lalr)
   #:export (next-token make-tokenizer make-tokenizer/1 tokenize tokenize/1))
 
 (define (syntax-error message . args)
@@ -75,8 +76,8 @@
           (lp (read-char port))))))
      (div?
       (case c1
-        ((#\=) (read-char port) `(/= . #f))
-        (else `(/ . #f))))
+        ((#\=) (read-char port) (make-lexical-token '/= #f #f))
+        (else (make-lexical-token '/ #f #f))))
      (else
       (read-regexp port)))))
 
@@ -95,7 +96,9 @@
                              (char-numeric? c)
                              (char=? c #\$)
                              (char=? c #\_))))
-                `(RegexpLiteral . (,(string-append head str) . ,(reverse flags)))
+                (make-lexical-token 'RegexpLiteral #f
+                                    (cons (string-append head str)
+                                          (reverse flags)))
                 (begin (read-char port)
                        (lp (peek-char port) (cons c flags))))))
          ((char=? terminator #\\)
@@ -216,7 +219,7 @@
     ("import" . import)
     ("public" . public)))
 
-(define (read-identifier port)
+(define (read-identifier port loc)
   (let lp ((c (peek-char port)) (chars '()))
     (if (or (eof-object? c)
             (not (or (char-alphabetic? c)
@@ -225,10 +228,11 @@
                      (char=? c #\_))))
         (let ((word (list->string (reverse chars))))
           (cond ((assoc-ref *keywords* word)
-                 => (lambda (x) `(,x . #f)))
+                 => (lambda (x) (make-lexical-token x loc #f)))
                 ((assoc-ref *future-reserved-words* word)
                  (syntax-error "word is reserved for the future, dude." word))
-                (else `(Identifier . ,(string->symbol word)))))
+                (else (make-lexical-token 'Identifier loc
+                                          (string->symbol word)))))
         (begin (read-char port)
                (lp (peek-char port) (cons c chars))))))
 
@@ -368,7 +372,7 @@
                            (else
                             (lp (cons (list (string-ref (caar puncs) 0) #f) nodes)
                                 puncs))))))
-    (lambda (port)
+    (lambda (port loc)
       (let lp ((c (peek-char port)) (tree punc-tree) (candidate #f))
         (cond
          ((assv-ref tree c)
@@ -376,15 +380,17 @@
                (read-char port)
                (lp (peek-char port) (cdr node-tail) (car node-tail))))
          (candidate
-          `(,candidate . #f))
+          (make-lexical-token candidate loc #f))
          (else
           (syntax-error "bad syntax: character not allowed" c)))))))
 
 (define (next-token port div?)
-  (let ((c (peek-char port))
-        (props `((filename . ,(port-filename port))
-                 (line . ,(port-line port))
-                 (column . ,(port-column port)))))
+  (let ((c   (peek-char port))
+        (loc (make-source-location (port-filename port)
+                                   (port-line port)
+                                   (port-column port)
+                                   (false-if-exception (seek port 0 SEEK_CUR))
+                                   #f)))
     (let ((tok 
            (case c
              ((#\ht #\vt #\np #\space)
@@ -400,7 +406,7 @@
               (read-slash port div?))
              ((#\" #\')
                                         ; string literal
-              `(StringLiteral . ,(read-string port)))
+              (make-lexical-token 'StringLiteral loc (read-string port)))
              (else
               (cond
                ((eof-object? c)
@@ -409,15 +415,14 @@
                     (char=? c #\$)
                     (char=? c #\_))
                 ;; reserved word or identifier
-                (read-identifier port))
+                (read-identifier port loc))
                ((char-numeric? c)
                 ;; numeric -- also accept . FIXME, requires lookahead
-                `(NumericLiteral . ,(read-numeric port)))
+                (make-lexical-token 'NumericLiteral loc (read-numeric port)))
                (else
                 ;; punctuation
-                (read-punctuation port)))))))
-      (if (pair? tok)
-          (set-source-properties! tok props))
+                (read-punctuation port loc)))))))
+
       tok)))
 
 (define (make-tokenizer port)
@@ -435,31 +440,32 @@
       (if eoi?
           '*eoi*
           (let ((tok (next-token port div?)))
-            (case (if (pair? tok) (car tok) tok)
+            (case (if (lexical-token? tok) (lexical-token-category tok) tok)
               ((lparen)
-               (set! stack (cons 'lparen stack)))
+               (set! stack (make-lexical-token 'lparen #f stack)))
               ((rparen)
                (if (and (pair? stack) (eq? (car stack) 'lparen))
                    (set! stack (cdr stack))
                    (syntax-error "unexpected right parenthesis")))
               ((lbracket)
-               (set! stack (cons 'lbracket stack)))
+               (set! stack (make-lexical-token 'lbracket #f stack)))
               ((rbracket)
                (if (and (pair? stack) (eq? (car stack) 'lbracket))
                    (set! stack (cdr stack))
                    (syntax-error "unexpected right bracket" stack)))
               ((lbrace)
-               (set! stack (cons 'lbrace stack)))
+               (set! stack (make-lexical-token 'lbrace #f stack)))
               ((rbrace)
                (if (and (pair? stack) (eq? (car stack) 'lbrace))
                    (set! stack (cdr stack))
                    (syntax-error "unexpected right brace" stack)))
               ((semicolon)
                (set! eoi? (null? stack))))
-            (set! div? (and (pair? tok)
-                            (or (eq? (car tok) 'Identifier)
-                                (eq? (car tok) 'NumericLiteral)
-                                (eq? (car tok) 'StringLiteral))))
+            (set! div? (and (lexical-token? tok)
+                            (let ((cat (lexical-token-category tok)))
+                              (or (eq? cat 'Identifier)
+                                  (eq? cat 'NumericLiteral)
+                                  (eq? cat 'StringLiteral)))))
             tok)))))
 
 (define (tokenize port)