Remove duplicate definitions of call/ec' and let/ec'.

* module/language/tree-il/peval.scm (let/ec): Remove. Import
  (ice-9 control).
* module/sxml/match.scm (%call/ec-prompt, call/ec, let/ec):
  Remove. Import (ice-9 control).

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

module/language/tree-il/peval.scm

@@ -26,6 +26,7 @@
   #:use-module (srfi srfi-9)
   #:use-module (srfi srfi-11)
   #:use-module (srfi srfi-26)
+  #:use-module (ice-9 control)
   #:export (peval))
 
 ;;;
@@ -73,15 +74,6 @@
     (newline)
     (values)))
 
-(define-syntax-rule (let/ec k e e* ...)
-  (let ((tag (make-prompt-tag)))
-    (call-with-prompt
-     tag
-     (lambda ()
-       (let ((k (lambda args (apply abort-to-prompt tag args))))
-         e e* ...))
-     (lambda (_ res) res))))
-
 (define (tree-il-any proc exp)
   (let/ec k
     (tree-il-fold (lambda (exp res)

module/sxml/match.scm

@@ -20,7 +20,8 @@
             sxml-match-let
             sxml-match-let*)
   #:use-module (srfi srfi-1)
-  #:use-module (srfi srfi-11))
+  #:use-module (srfi srfi-11)
+  #:use-module (ice-9 control))
 
 
 ;;; Commentary:
@@ -46,22 +47,6 @@
 (define-syntax-rule (void)
   *unspecified*)
 
-(define %call/ec-prompt
-  (make-prompt-tag))
-
-(define-syntax-rule (call/ec proc)
-  ;; aka. `call-with-escape-continuation'
-  (call-with-prompt %call/ec-prompt
-                    (lambda ()
-                      (proc (lambda args
-                              (apply abort-to-prompt
-                                     %call/ec-prompt args))))
-                    (lambda (_ . args)
-                      (apply values args))))
-
-(define-syntax-rule (let/ec cont body ...)
-  (call/ec (lambda (cont) body ...)))
-
 (define (raise-syntax-error x msg obj sub)
   (throw 'sxml-match-error x msg obj sub))