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* guile.texi: Commented out menu entry and inclusion of Tcl/Tk

Browse source 
stuff.

	* indices.texi: Users are advised to look under C and Scheme
	names, xref to transformation rules added.

	* intro.texi, scheme-modules.texi, scheme-ideas.texi,
	scheme-evaluation.texi, scheme-data.texi, scheme-procedures.texi:
	Fixed most REFFIXMEs.

	* srfi-modules.texi (About SRFI Usage): New node.
	(SRFI-0): Extended.
	Fixed all REFFIXMEs.
This commit is contained in:
Martin Grabmüller 2001-05-23 17:24:50 +00:00
parent 60a54e2fca
commit 92905faf2c
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16
doc/ChangeLog
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@ -1,3 +1,19 @@
2001-05-23 Martin Grabmueller <mgrabmue@cs.tu-berlin.de>
* guile.texi: Commented out menu entry and inclusion of Tcl/Tk
stuff.
* indices.texi: Users are advised to look under C and Scheme
names, xref to transformation rules added.
* intro.texi, scheme-modules.texi, scheme-ideas.texi,
scheme-evaluation.texi, scheme-data.texi, scheme-procedures.texi:
Fixed most REFFIXMEs.
* srfi-modules.texi (About SRFI Usage): New node.
(SRFI-0): Extended.
Fixed all REFFIXMEs.
2001-05-19 Neil Jerram <neil@ossau.uklinux.net>
* posix.texi (Networking): Split existing material into new nodes

6
doc/guile.texi
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@ -80,7 +80,7 @@ by the Free Software Foundation.
@sp 10
@comment The title is printed in a large font.
@title Guile Reference Manual
@subtitle $Id: guile.texi,v 1.9 2001-05-14 21:37:51 mgrabmue Exp $
@subtitle $Id: guile.texi,v 1.10 2001-05-23 17:24:49 mgrabmue Exp $
@subtitle For use with Guile @value{VERSION}
@include AUTHORS
@ -177,7 +177,7 @@ Part III: Guile Modules
add-on, so maybe it shouldn't be documented here
(though it is nice to have a link from here to the
Guile-scsh manual, if one exists).
* Tcl/Tk Interface::
@c * Tcl/Tk Interface::
Part IV: Guile Scripting
@ -255,7 +255,7 @@ Indices
@include repl-modules.texi
@include expect.texi
@include scsh.texi
@include tcltk.texi
@c @include tcltk.texi
@c Guile as an scripting language
@iftex

28
doc/indices.texi
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@ -1,22 +1,40 @@
@node Concept Index
@unnumbered Concept Index
This index contains concepts, keywords and non-Schemey names for several
features, to make it easier to locate the desired sections.
@printindex cp
@node Procedure Index
@unnumbered Procedure Index
@c FIXME::martin: Review me!
This is an alphabetical list of all the procedures and macros in Guile.
[[Remind people to look for functions under their Scheme names as well
as their C names.]]
When looking for a particular procedure, please look under its Scheme
name as well as under its C name. The C name can be constructed from
the Scheme names by a simple transformation described in the section
@xref{Transforming Scheme name to C name}.
@printindex fn
@node Variable Index
@unnumbered Variable Index
@c FIXME::martin: Review me!
This is an alphabetical list of all the important variables and
constants in Guile.
[[Remind people to look for variables under their Scheme names as well
as their C names.]]
When looking for a particular variable or constant, please look under
its Scheme name as well as under its C name. The C name can be
constructed from the Scheme names by a simple transformation described
in the section @xref{Transforming Scheme name to C name}.
@printindex vr
@ -25,7 +43,9 @@ as their C names.]]
@c spurious makeinfo errors.
@node Type Index
@unnumbered Type Index
This is an alphabetical list of all the important data types defined in
the Guile Programmers Manual.
@printindex tp

4
doc/intro.texi
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@ -1,4 +1,4 @@
@c $Id: intro.texi,v 1.9 2001-05-16 18:08:12 mgrabmue Exp $
@c $Id: intro.texi,v 1.10 2001-05-23 17:24:49 mgrabmue Exp $
@page
@node What is Guile?
@ -686,7 +686,7 @@ usual for your operating system, and it will additionally look into the
directories listed in the @code{LTDL_LIBRRAY_PATH} environment variable.
To see how these Guile extensions via shared libraries relate to the
module system, see below REFFIXME.
module system, see below @xref{Intro to Modules and Extensions}.
@node Guile Modules
@section Guile Modules

18
doc/scheme-data.texi
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@ -1614,9 +1614,10 @@ y
@subsection String Comparison
The procedures in this section are similar to the character ordering
predicates (REFFIXME), but are defined on character sequences. They all
return @code{#t} on success and @code{#f} on failure. The predicates
ending in @code{-ci} ignore the character case when comparing strings.
predicates (@pxref{Characters}), but are defined on character sequences.
They all return @code{#t} on success and @code{#f} on failure. The
predicates ending in @code{-ci} ignore the character case when comparing
strings.
@rnindex string=?
@ -2536,7 +2537,7 @@ one of the constructor procedures @code{make-variable} or
@code{make-undefined-variable} or retrieved by @code{builtin-variable}.
First-class variables are especially useful for interacting with the
current module system (REFFIXME).
current module system (@pxref{The Guile module system}).
@deffn primitive builtin-variable name
Return the built-in variable with the name @var{name}.
@ -2967,7 +2968,7 @@ up a list. An example will clear that up:
This example also shows that lists have to be quoted (REFFIXME) when
written, because they would otherwise be mistakingly taken as procedure
applications (REFFIXME).
applications (@pxref{Simple Invocation}).
@node List Predicates
@ -3028,7 +3029,7 @@ that modifying the elements of the new list also modyfies the elements
of the old list. On the other hand, applying procedures like
@code{set-cdr!} or @code{delv!} to the new list will not alter the old
list. If you also need to copy the list elements (making a deep copy),
use the procedure @code{copy-tree} (REFFIXME).
use the procedure @code{copy-tree} (@pxref{Copying}).
@node List Selection
@subsection List Selection
@ -4896,8 +4897,9 @@ elements of @var{vector}.
@subsection Vector Modification
A vector created by any of the vector constructor procedures (REFFIXME)
documented above can be modified using the following procedures.
A vector created by any of the vector constructor procedures
(@pxref{Vectors}) documented above can be modified using the
following procedures.
According to R5RS, using any of these procedures on literally entered
vectors is an error, because these vectors are considered to be

12
doc/scheme-evaluation.texi
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@ -72,10 +72,10 @@ another comment type for multiline comments, called @dfn{block
comments}. This type of comment begins with the character sequence
@code{#!} and ends with the characters @code{!#}, which must appear on a
line of their own. These comments are compatible with the block
comments in the Scheme Shell @file{scsh} (REFFIXME). The characters
@code{#!} were chosen because they are the magic characters used in
shell scripts for indicating that the name of the program for executing
the script follows on the same line.
comments in the Scheme Shell @file{scsh} (@pxref{The Scheme shell
(scsh)}). The characters @code{#!} were chosen because they are the
magic characters used in shell scripts for indicating that the name of
the program for executing the script follows on the same line.
Thus a Guile script often starts like this.
@ -85,7 +85,7 @@ Thus a Guile script often starts like this.
@end lisp
More details on Guile scripting can be found in the scripting section
(REFFIXME).
(@pxref{Guile Scripting}).
@node Case Sensitivity
@ -105,7 +105,7 @@ are the same in R5RS Scheme, but are different in Guile.
It is possible to turn off case sensitivity in Guile by setting the
reader option @code{case-insensitive}. More on reader options can be
found at (REFFIXME).
found at (@pxref{Reader options}).
@lisp
(read-enable 'case-insensitive)

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20
doc/scheme-modules.texi
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@ -394,38 +394,38 @@ Mikael Djurfeldt's source-level debugging support for Guile
Guile's support for multi threaded execution (@pxref{Scheduling}).
@item (ice-9 rdelim)
Line- and character-delimited input (REFFIXME).
Line- and character-delimited input (@pxref{Line/Delimited}).
@item (ice-9 documentation)
Online documentation (REFFIXME).
@item (srfi srfi-2)
Support for @code{and-let*} (REFFIXME).
Support for @code{and-let*} (@pxref{SRFI-2}).
@item (srfi srfi-6)
Support for some additional string port procedures (REFFIXME).
Support for some additional string port procedures (@pxref{SRFI-6}).
@item (srfi srfi-8)
Multiple-value handling with @code{receive} (REFFIXME).
Multiple-value handling with @code{receive} (@pxref{SRFI-8}).
@item (srfi srfi-9)
Record definition with @code{define-record-type} (REFFIXME).
Record definition with @code{define-record-type} (@pxref{SRFI-9}).
@item (srfi srfi-10)
Read hash extension @code{#,()} (REFFIXME).
Read hash extension @code{#,()} (@pxref{SRFI-10}).
@item (srfi srfi-11)
Multiple-value handling with @code{let-values} and @code{let-values*}
(REFFIXME).
(@pxref{SRFI-11}).
@item (srfi srfi-13)
String library (REFFIXME).
String library (@pxref{SRFI-13}).
@item (srfi srfi-14)
Character-set library (REFFIXME).
Character-set library (@pxref{SRFI-14}).
@item (srfi srfi-17)
Getter-with-setter support (REFFIXME).
Getter-with-setter support (@pxref{SRFI-17}).
@item (ice-9 slib)
This module contains hooks for using Aubrey Jaffer's portable Scheme

779
doc/scheme-procedures.texi
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@ -1,779 +0,0 @@
@page
@node Procedures and Macros
@chapter Procedures and Macros
@menu
* Lambda:: Basic procedure creation using lambda.
* Optional Arguments:: Handling keyword, optional and rest arguments.
* Procedure Properties:: Procedure properties and metainformation.
* Procedures with Setters:: Procedures with setters.
* Macros:: Lisp style macro definitions.
* Syntax Rules:: Support for R5RS @code{syntax-rules}.
* Syntax Case:: Support for the @code{syntax-case} system.
* Internal Macros:: Guile's internal representation.
@end menu
@node Lambda
@section Lambda: Basic Procedure Creation
@c FIXME::martin: Review me!
A @code{lambda} expression evaluates to a procedure. The environment
which is in effect when a @code{lambda} expression is evaluated is
enclosed in the newly created procedure, this is referred to as a
@dfn{closure} (@pxref{About Closure}).
When a procedure created by @code{lambda} is called with some actual
arguments, the environment enclosed in the procedure is extended by
binding the variables named in the formal argument list to new locations
and storing the actual arguments into these locations. Then the body of
the @code{lambda} expression is evaluation sequentially. The result of
the last expression in the procedure body is then the result of the
procedure invocation.
The following examples will show how procedures can be created using
@code{lambda}, and what you can do with these procedures.
@lisp
(lambda (x) (+ x x)) @result{} @r{a procedure}
((lambda (x) (+ x x)) 4) @result{} 8
@end lisp
The fact that the environment in effect when creating a procedure is
enclosed in the procedure is shown with this example:
@lisp
(define add4
(let ((x 4))
(lambda (y) (+ x y))))
(add4 6) @result{} 10
@end lisp
@deffn syntax lambda formals body
@var{formals} should be a formal argument list as described in the
following table.
@table @code
@item (@var{variable1} @dots{})
The procedure takes a fixed number of arguments; when the procedure is
called, the arguments will be stored into the newly created location for
the formal variables.
@item @var{variable}
The procedure takes any number of arguments; when the procedure is
called, the sequence of actual arguments will converted into a list and
stored into the newly created location for the formal variable.
@item (@var{variable1} @dots{} @var{variablen} . @var{variablen+1})
If a space-delimited period precedes the last variable, then the
procedure takes @var{n} or more variablesm where @var{n} is the number
of formal arguments before the period. There must be at least one
argument before the period. The first @var{n} actual arguments will be
stored into the newly allocated locations for the first @var{n} formal
arguments and the sequence of the remaining actual arguments is
converted into a list and the stored into the location for the last
formal argument. If there are exactly @var{n} actual arguments, the
empty list is stored into the location of the last formal argument.
@end table
@var{body} is a sequence of Scheme expressions which are evaluated in
order when the procedure is invoked.
@end deffn
@node Optional Arguments
@section Optional Arguments
@c FIXME::martin: Review me!
Scheme procedures, as defined in R5RS, can wither handle a fixed number
of actual arguments, or a fixed number of actual arguments followed by
arbitrarily many additional arguments. Writing procedures of variable
arity can be useful, but unfortunately, the syntactic means for handling
argument lists of varying length is a bit inconvenient. It is possible
to give names to the fixed number of argument, but the remaining
(optional) arguments can be only referenced as a list of values
(@pxref{Lambda}).
Guile comes with the module @code{(ice-9 optargs)}, which makes using
optional arguments much more convenient. In addition, this module
provides syntax for handling keywords in argument lists
(@pxref{Keywords}).
Before using any of the procedures or macros defined in this section,
you have to load the module @code{(ice-9 optargs)} with the statement:
@lisp
(use-modules (ice-9 optargs))
@end lisp
@menu
* let-optional Reference:: Locally binding optional arguments.
* let-keywords Reference:: Locally binding keywords arguments.
* lambda* Reference:: Creating advanced argument handling procedures.
* define* Reference:: Defining procedures and macros.
@end menu
@node let-optional Reference
@subsection let-optional Reference
@c FIXME::martin: Review me!
The syntax @code{let-optional} and @code{let-optional*} are for
destructuring rest argument lists and giving names to the various list
elements. @code{let-optional} binds all variables simultaneously, while
@code{let-optional*} binds them sequentially, consistent with @code{let}
and @code{let*} (REFFIXME).
@deffn {libary syntax} let-optional rest-arg (binding @dots{}) expr @dots{}
@deffnx {library syntax} let-optional* rest-arg (binding @dots{}) expr @dots{}
These two macros give you an optional argument interface that is very
@dfn{Schemey} and introduces no fancy syntax. They are compatible with
the scsh macros of the same name, but are slightly extended. Each of
@var{binding} may be of one of the forms @var{var} or @code{(@var{var}
@var{default-value})}. @var{rest-arg} should be the rest-argument of the
procedures these are used from. The items in @var{rest-arg} are
sequentially bound to the variable names are given. When @var{rest-arg}
runs out, the remaining vars are bound either to the default values or
left unbound if no default value was specified. @var{rest-arg} remains
bound to whatever may have been left of @var{rest-arg}.
After binding the variables, the expressions @var{expr} @dots{} are
evaluated in order.
@end deffn
@node let-keywords Reference
@subsection let-keywords Reference
@c FIXME::martin: Review me!
@code{let-keywords} and @code{let-keywords*} are used for extracting
values from argument lists which use keywords instead of argument
position for binding local variables to argument values.
@code{let-keywords} binds all variables simultaneously, while
@code{let-keywords*} binds them sequentially, consistent with @code{let}
and @code{let*} (REFFIXME).
@deffn {library syntax} let-keywords rest-arg allow-other-keys? (binding @dots{}) expr @dots{}
@deffnx {library syntax} let-keywords rest-arg allow-other-keys? (binding @dots{}) expr @dots{}
These macros pick out keyword arguments from @var{rest-arg}, but do not
modify it. This is consistent at least with Common Lisp, which
duplicates keyword arguments in the rest argument. More explanation of what
keyword arguments in a lambda list look like can be found below in
the documentation for @code{lambda*}
(@pxref{lambda* Reference}). @var{binding}s can have the same form as
for @code{let-optional}. If @var{allow-other-keys?} is false, an error
will be thrown if anything that looks like a keyword argument but does
not match a known keyword parameter will result in an error.
After binding the variables, the expressions @var{expr} @dots{} are
evaluated in order.
@end deffn
@node lambda* Reference
@subsection lambda* Reference
@c FIXME::martin: Review me!
When using optional and keyword argument lists, using @code{lambda} for
creating procedures and using @code{let-optional} or @code{let-keywords}
is a bit lengthy. Therefore, @code{lambda*} is provided, which combines
the features of those macros into a single convenient syntax.
For quick reference, here is the syntax of the formal argument list for
@code{lambda*} (brackets are used to indicate grouping only):
@example
ext-param-list ::= [identifier]* [#:optional [ext-var-decl]+]?
[#:key [ext-var-decl]+ [#:allow-other-keys]?]?
[[#:rest identifier]|[. identifier]]?
ext-var-decl ::= identifier | ( identifier expression )
@end example
The characters `*', `+' and `?' are not to be taken literally; they mean
respectively, zero or more occurences, one or more occurences, and one
or zero occurences.
@deffn {library syntax} lambda* formals body
@code{lambda*} creates a procedure that takes optional arguments. These
are specified by putting them inside brackets at the end of the
paramater list, but before any dotted rest argument. For example,
@lisp
(lambda* (a b #:optional c d . e) '())
@end lisp
creates a procedure with fixed arguments @var{a} and @var{b}, optional
arguments @var{c} and @var{d}, and rest argument @var{e}. If the
optional arguments are omitted in a call, the variables for them are
unbound in the procedure. This can be checked with the @code{bound?}
macro (documented below).
@code{lambda*} can also take keyword arguments. For example, a procedure
defined like this:
@lisp
(lambda* (#:key xyzzy larch) '())
@end lisp
can be called with any of the argument lists @code{(#:xyzzy 11)}
@code{(#:larch 13)} @code{(#:larch 42 #:xyzzy 19)} @code{()}. Whichever
arguments are given as keywords are bound to values.
Optional and keyword arguments can also be given default values
which they take on when they are not present in a call, by giving a
two-item list in place of an optional argument, for example in:
@lisp
(lambda* (foo #:optional (bar 42) #:key (baz 73))
(list foo bar baz))
@end lisp
@var{foo} is a fixed argument, @var{bar} is an optional argument with
default value 42, and baz is a keyword argument with default value 73.
Default value expressions are not evaluated unless they are needed and
until the procedure is called.
@code{lambda*} also supports two more special parameter list keywords.
@code{lambda*}-defined procedures now throw an error by default if a
keyword other than one of those specified is found in the actual
passed arguments. However, specifying @code{#:allow-other-keys}
immediately after the keyword argument declarations restores the
previous behavior of ignoring unknown keywords. @code{lambda*} also now
guarantees that if the same keyword is passed more than once, the
last one passed is the one that takes effect. For example,
@lisp
((lambda* (#:key (heads 0) (tails 0)) (display (list heads tails)))
#:heads 37 #:tails 42 #:heads 99)
@end lisp
would result in (99 47) being displayed.
@code{#:rest} is also now provided as a synonym for the dotted syntax
rest argument. The argument lists @code{(a . b)} and @code{(a #:rest b)}
are equivalent in all respects to @code{lambda*}. This is provided for
more similarity to DSSSL, MIT-Scheme and Kawa among others, as well as
for refugees from other Lisp dialects.
@end deffn
@deffn {library syntax} bound? variable
Check if a variable is bound in the current environment.
The procedure @code{defined?} doesn't quite cut it as it stands, since
it only checks bindings in the top-level environment, not those in local
scope only.
@end deffn
@node define* Reference
@subsection define* Reference
@c FIXME::martin: Review me!
Just like @code{define} has a shorthand notation for defining procedures
(@pxref{Lambda Alternatives}), @code{define*} is provided as an
abbreviation of the combination of @code{define} and @code{lambda*}.
@code{define*-public} is the @code{lambda*} version of
@code{define-public}; @code{defmacro*} and @code{defmacro*-public} exist
for defining macros with the improved argument list handling
possibilities. The @code{-public} versions not only define the
procedures/macros, but also export them from the current module.
@deffn {library syntax} define* formals body
@deffnx {library syntax} define*-public formals body
@code{define*} and @code{define*-public} support optional arguments with
a similar syntax to @code{lambda*}. They also support arbitrary-depth
currying, just like Guile's define. Some examples:
@lisp
(define* (x y #:optional a (z 3) #:key w . u)
(display (list y z u)))
@end lisp
defines a procedure @code{x} with a fixed argument @var{y}, an optional
agument @var{a}, another optional argument @var{z} with default value 3,
a keyword argument @var{w}, and a rest argument @var{u}.
@lisp
(define-public* ((foo #:optional bar) #:optional baz) '())
@end lisp
This illustrates currying. A procedure @code{foo} is defined, which,
when called with an optional argument @var{bar}, returns a procedure
that takes an optional argument @var{baz}.
Of course, @code{define*[-public]} also supports @code{#:rest} and
@code{#:allow-other-keys} in the same way as @code{lambda*}.
@end deffn
@deffn {library syntax} defmacro* name formals body
@deffnx {library syntax} defmacro*-public name formals body
These are just like @code{defmacro} and @code{defmacro-public} except that they
take @code{lambda*}-style extended paramter lists, where @code{#:optional},
@code{#:key}, @code{#:allow-other-keys} and @code{#:rest} are allowed with the usual
semantics. Here is an example of a macro with an optional argument:
@lisp
(defmacro* transmorgify (a #:optional b)
(a 1))
@end lisp
@end deffn
@node Procedure Properties
@section Procedure Properties and Metainformation
@c FIXME::martin: Review me!
Procedures always have attached the environment in which they were
created and information about how to apply them to actual arguments. In
addition to that, properties and metainformation can be stored with
procedures. The procedures in this section can be used to test whether
a given procedure satisfies a condition; and to access and set a
procedure's property.
The first group of procedures are predicates to test whether a Scheme
object is a procedure, or a special procedure, respectively.
@code{procedure?} is the most general predicates, it returns @code{#t}
for any kind of procedure. @code{closure?} does not return @code{#t}
for primitive procedures, and @code{thunk?} only returns @code{#t} for
procedures which do not accept any arguments.
@c FIXME::martin: thunk? returns true for `id'. What's wrong here?
@rnindex procedure?
@deffn primitive procedure? obj
Return @code{#t} if @var{obj} is a procedure.
@end deffn
@deffn primitive closure? obj
Return @code{#t} if @var{obj} is a closure.
@end deffn
@deffn primitive thunk? obj
Return @code{#t} if @var{obj} is a thunk.
@end deffn
@c FIXME::martin: Is that true?
@cindex procedure properties
Procedure properties are general properties to be attached to
procedures. These can be the name of a procedure or other relevant
information, such as debug hints.
@deffn primitive procedure-properties proc
Return @var{obj}'s property list.
@end deffn
@deffn primitive procedure-property p k
Return the property of @var{obj} with name @var{key}.
@end deffn
@deffn primitive set-procedure-properties! proc new_val
Set @var{obj}'s property list to @var{alist}.
@end deffn
@deffn primitive set-procedure-property! p k v
In @var{obj}'s property list, set the property named @var{key} to
@var{value}.
@end deffn
@cindex procedure documentation
Documentation for a procedure can be accessed with the procedure
@code{procedure-documentation}.
@deffn primitive procedure-documentation proc
Return the documentation string associated with @code{proc}. By
convention, if a procedure contains more than one expression and the
first expression is a string constant, that string is assumed to contain
documentation for that procedure.
@end deffn
@cindex source properties
@c FIXME::martin: Is the following true?
Source properties are properties which are related to the source code of
a procedure, such as the line and column numbers, the file name etc.
@deffn primitive set-source-properties! obj plist
Install the association list @var{plist} as the source property
list for @var{obj}.
@end deffn
@deffn primitive set-source-property! obj key datum
Set the source property of object @var{obj}, which is specified by
@var{key} to @var{datum}. Normally, the key will be a symbol.
@end deffn
@deffn primitive source-properties obj
Return the source property association list of @var{obj}.
@end deffn
@deffn primitive source-property obj key
Return the source property specified by @var{key} from
@var{obj}'s source property list.
@end deffn
@node Procedures with Setters
@section Procedures with Setters
@c FIXME::martin: Review me!
@c FIXME::martin: Document `operator struct'.
@cindex procedure with setter
@cindex setter
A @dfn{procedure with setter} is a special kind of procedure which
normally behaves like any accesor procedure, that is a procedure which
accesses a data structure. The difference is that this kind of
procedure has a so-called @dfn{setter} attached, which is a procedure
for storing something into a data structure.
Procedures with setters are treated specially when the procedure appears
in the special form @code{set!} (REFFIXME). How it works is best shown
by example.
Suppose we have a procedure called @code{foo-ref}, which accepts two
arguments, a value of type @code{foo} and an integer. The procedure
returns the value stored at the given index in the @code{foo} object.
Let @code{f} be a variable containing such a @code{foo} data
structure.@footnote{Working definitions would be:
@lisp
(define foo-ref vector-ref)
(define foo-set! vector-set!)
(define f (make-vector 2 #f))
@end lisp
}
@lisp
(foo-ref f 0) @result{} bar
(foo-ref f 1) @result{} braz
@end lisp
Also suppose that a corresponding setter procedure called
@code{foo-set!} does exist.
@lisp
(foo-set! f 0 'bla)
(foo-ref f 0) @result{} bla
@end lisp
Now we could create a new procedure called @code{foo}, which is a
procedure with setter, by calling @code{make-procedure-with-setter} with
the accessor and setter procedures @code{foo-ref} and @code{foo-set!}.
Let us call this new procedure @code{foo}.
@lisp
(define foo (make-procedure-with-setter foo-ref foo-set!))
@end lisp
@code{foo} can from now an be used to either read from the data
structure stored in @code{f}, or to write into the structure.
@lisp
(set! (foo f 0) 'dum)
(foo f 0) @result{} dum
@end lisp
@deffn primitive make-procedure-with-setter procedure setter
Create a new procedure which behaves like @var{procedure}, but
with the associated setter @var{setter}.
@end deffn
@deffn primitive procedure-with-setter? obj
Return @code{#t} if @var{obj} is a procedure with an
associated setter procedure.
@end deffn
@deffn primitive procedure proc
Return the procedure of @var{proc}, which must be either a
procedure with setter, or an operator struct.
@end deffn
@deffn primitive setter proc
Return the setter of @var{proc}, which must be either a procedure with
setter or an operator struct.
@end deffn
@node Macros
@section Lisp Style Macro Definitions
@cindex macros
@cindex transformation
Macros are objects which cause the expression that they appear in to be
transformed in some way @emph{before} being evaluated. In expressions
that are intended for macro transformation, the identifier that names
the relevant macro must appear as the first element, like this:
@lisp
(@var{macro-name} @var{macro-args} @dots{})
@end lisp
In Lisp-like languages, the traditional way to define macros is very
similar to procedure definitions. The key differences are that the
macro definition body should return a list that describes the
transformed expression, and that the definition is marked as a macro
definition (rather than a procedure definition) by the use of a
different definition keyword: in Lisp, @code{defmacro} rather than
@code{defun}, and in Scheme, @code{define-macro} rather than
@code{define}.
@fnindex defmacro
@fnindex define-macro
Guile supports this style of macro definition using both @code{defmacro}
and @code{define-macro}. The only difference between them is how the
macro name and arguments are grouped together in the definition:
@lisp
(defmacro @var{name} (@var{args} @dots{}) @var{body} @dots{})
@end lisp
@noindent
is the same as
@lisp
(define-macro (@var{name} @var{args} @dots{}) @var{body} @dots{})
@end lisp
@noindent
The difference is analogous to the corresponding difference between
Lisp's @code{defun} and Scheme's @code{define}.
@code{false-if-exception}, from the @file{boot-9.scm} file in the Guile
distribution, is a good example of macro definition using
@code{defmacro}:
@lisp
(defmacro false-if-exception (expr)
`(catch #t
(lambda () ,expr)
(lambda args #f)))
@end lisp
@noindent
The effect of this definition is that expressions beginning with the
identifier @code{false-if-exception} are automatically transformed into
a @code{catch} expression following the macro definition specification.
For example:
@lisp
(false-if-exception (open-input-file "may-not-exist"))
@equiv{}
(catch #t
(lambda () (open-input-file "may-not-exist"))
(lambda args #f))
@end lisp
@node Syntax Rules
@section The R5RS @code{syntax-rules} System
R5RS defines an alternative system for macro and syntax transformations
using the keywords @code{define-syntax}, @code{let-syntax},
@code{letrec-syntax} and @code{syntax-rules}.
The main difference between the R5RS system and the traditional macros
of the previous section is how the transformation is specified. In
R5RS, rather than permitting a macro definition to return an arbitrary
expression, the transformation is specified in a pattern language that
@itemize @bullet
@item
does not require complicated quoting and extraction of components of the
source expression using @code{caddr} etc.
@item
is designed such that the bindings associated with identifiers in the
transformed expression are well defined, and such that it is impossible
for the transformed expression to construct new identifiers.
@end itemize
@noindent
The last point is commonly referred to as being @dfn{hygienic}: the R5RS
@code{syntax-case} system provides @dfn{hygienic macros}.
For example, the R5RS pattern language for the @code{false-if-exception}
example of the previous section looks like this:
@lisp
(syntax-rules ()
((_ expr)
(catch #t
(lambda () expr)
(lambda args #f))))
@end lisp
In Guile, the @code{syntax-rules} system is provided by the @code{(ice-9
syncase)} module. To make these facilities available in your code,
include the expression @code{(use-modules (ice-9 syncase))} or
@code{(use-syntax (ice-9 syncase))} (@pxref{Using Guile Modules})
before the first usage of @code{define-syntax} etc. If you are writing
a Scheme module, you can alternatively use one of the keywords
@code{#:use-module} and @code{#:use-syntax} in your @code{define-module}
declaration (@pxref{Creating Guile Modules}).
@menu
* Pattern Language:: The @code{syntax-rules} pattern language.
* Define-Syntax:: Top level syntax definitions.
* Let-Syntax:: Local syntax definitions.
@end menu
@node Pattern Language
@subsection The @code{syntax-rules} Pattern Language
@node Define-Syntax
@subsection Top Level Syntax Definitions
define-syntax: The gist is
(define-syntax <keyword> <transformer-spec>)
makes the <keyword> into a macro so that
(<keyword> ...)
expands at _compile_ or _read_ time (i.e. before any
evaluation begins) into some expression that is
given by the <transformer-spec>.
@node Let-Syntax
@subsection Local Syntax Definitions
@node Syntax Case
@section Support for the @code{syntax-case} System
@node Internal Macros
@section Internal Representation of Macros and Syntax
Internally, Guile uses three different flavours of macros. The three
flavours are called @dfn{acro} (or @dfn{syntax}), @dfn{macro} and
@dfn{mmacro}.
Given the expression
@lisp
(foo @dots{})
@end lisp
@noindent
with @code{foo} being some flavour of macro, one of the following things
will happen when the expression is evaluated.
@itemize @bullet
@item
When @code{foo} has been defined to be an @dfn{acro}, the procedure used
in the acro definition of @code{foo} is passed the whole expression and
the current lexical environment, and whatever that procedure returns is
the value of evaluating the expression. You can think of this a
procedure that receives its argument as an unevaluated expression.
@item
When @code{foo} has been defined to be a @dfn{macro}, the procedure used
in the macro definition of @code{foo} is passed the whole expression and
the current lexical environment, and whatever that procedure returns is
evaluated again. That is, the procedure should return a valid Scheme
expression.
@item
When @code{foo} has been defined to be a @dfn{mmacro}, the procedure
used in the mmacro definition of `foo' is passed the whole expression
and the current lexical environment, and whatever that procedure returns
replaces the original expression. Evaluation then starts over from the
new expression that has just been returned.
@end itemize
The key difference between a @dfn{macro} and a @dfn{mmacro} is that the
expression returned by a @dfn{mmacro} procedure is remembered (or
@dfn{memoized}) so that the expansion does not need to be done again
next time the containing code is evaluated.
The primitives @code{procedure->syntax}, @code{procedure->macro} and
@code{procedure->memoizing-macro} are used to construct acros, macros
and mmacros respectively. However, if you do not have a very special
reason to use one of these primitives, you should avoid them: they are
very specific to Guile's current implementation and therefore likely to
change. Use @code{defmacro}, @code{define-macro} (@pxref{Macros}) or
@code{define-syntax} (@pxref{Syntax Rules}) instead. (In low level
terms, @code{defmacro}, @code{define-macro} and @code{define-syntax} are
all implemented as mmacros.)
@deffn primitive procedure->syntax code
Return a macro which, when a symbol defined to this value appears as the
first symbol in an expression, returns the result of applying @var{code}
to the expression and the environment.
@end deffn
@deffn primitive procedure->macro code
Return a macro which, when a symbol defined to this value appears as the
first symbol in an expression, evaluates the result of applying
@var{code} to the expression and the environment. For example:
@lisp
(define trace
(procedure->macro
(lambda (x env)
`(set! ,(cadr x) (tracef ,(cadr x) ',(cadr x))))))
(trace @i{foo})
@equiv{}
(set! @i{foo} (tracef @i{foo} '@i{foo})).
@end lisp
@end deffn
@deffn primitive procedure->memoizing-macro code
Return a macro which, when a symbol defined to this value appears as the
first symbol in an expression, evaluates the result of applying
@var{code} to the expression and the environment.
@code{procedure->memoizing-macro} is the same as
@code{procedure->macro}, except that the expression returned by
@var{code} replaces the original macro expression in the memoized form
of the containing code.
@end deffn
In the following primitives, @dfn{acro} flavour macros are referred to
as @dfn{syntax transformers}.
@deffn primitive macro? obj
Return @code{#t} if @var{obj} is a regular macro, a memoizing macro or a
syntax transformer.
@end deffn
@deffn primitive macro-type m
Return one of the symbols @code{syntax}, @code{macro} or
@code{macro!}, depending on whether @var{m} is a syntax
transformer, a regular macro, or a memoizing macro,
respectively. If @var{m} is not a macro, @code{#f} is
returned.
@end deffn
@deffn primitive macro-name m
Return the name of the macro @var{m}.
@end deffn
@deffn primitive macro-transformer m
Return the transformer of the macro @var{m}.
@end deffn
@deffn primitive cons-source xorig x y
Create and return a new pair whose car and cdr are @var{x} and @var{y}.
Any source properties associated with @var{xorig} are also associated
with the new pair.
@end deffn
@c Local Variables:
@c TeX-master: "guile.texi"
@c End:

98
doc/srfi-modules.texi
View file

@ -1,6 +1,6 @@
@page
@node SRFI Support
@chapter Various SRFI Support Modules
@chapter SRFI Support Modules
SRFI is an acronym for Scheme Request For Implementation. The SRFI
documents define a lot of syntactic and procedure extensions to standard
@ -13,6 +13,7 @@ get the relevant SRFI documents from the SRFI home page
@url{http://srfi.schemers.org}.
@menu
* About SRFI Usage:: What to know about Guile's SRFI support.
* SRFI-0:: cond-expand
* SRFI-2:: and-let*.
* SRFI-6:: Basic String Ports.
@ -27,6 +28,40 @@ get the relevant SRFI documents from the SRFI home page
@end menu
@node About SRFI Usage
@section About SRFI Usage
@c FIXME::martin: Review me!
SRFI support in Guile is currently implemented partly in the core
library, and partly as add-on modules. That means that some SRFIs are
automatically available when the interpreter is started, whereas the
other SRFIs require you to use the appropriate support module
explicitly.
There are several reasons for this inconsistency. First, the feature
checking syntactic form @code{cond-expand} (@pxref{SRFI-0}) must be
available immediately, because it must be there when the user wants to
check for the Scheme implementation, that is, before she can know that
it is safe to use @code{use-modules} to load SRFI support modules. The
second reason is that some features defined in SRFIs had been
implemented in Guile before the developers started to add SRFI
implementations as modules (for example SRFI-6 (@pxref{SRFI-6})). In
the future, it is possible that SRFIs in the core library might be
factored out into separate modules, requiring explicit module loading
when they are needed. So you should be prepared to have to use
@code{use-modules} someday in the future to access SRFI-6 bindings. If
you want, you can do that already. We have included the module
@code{(srfi srfi-6)} in the distribution, which currently does nothing,
but ensures that you can write future-safe code.
Generally, support for a specific SRFI is made available by using
modules named @code{(srfi srfi-@var{number})}, where @var{number} is the
number of the SRFI needed. Another possibility is to use the command
line option @code{--use-srfi}, which will load the necessary modules
automatically (@pxref{Invoking Guile}).
@node SRFI-0
@section SRFI-0 - cond-expand
@ -78,6 +113,8 @@ If the feature requirement is the keyword @code{else} and it is the last
clause, it is satisfied if no prior clause matched.
@end itemize
If no clause is satisfied, an error is signalled.
Since @code{cond-expand} is needed to tell what a Scheme implementation
provides, it must be accessible without using any
implementation-dependant operations, such as @code{use-modules} in
@ -85,11 +122,13 @@ Guile. Thus, it is not necessary to use any module to get access to
this form.
Currently, the feature identifiers @code{guile}, @code{r5rs} and
@code{srfi-0} are supported. The other SRFIs are not in that list,
because the SRFI modules must be explicitly used before their exported
bindings can be used. So if a Scheme program wishes to detect whether
SRFI-8 is supported in the running implementation, code similar to this
may be needed:
@code{srfi-0} are supported. The other SRFIs are not in that list by
default, because the SRFI modules must be explicitly used before their
exported bindings can be used.
So if a Scheme program wishes to use SRFI-8, it has two possibilities:
First, it can check whether the running Scheme implementation is Guile,
and if it is, it can use the appropriate module:
@lisp
(cond-expand
@ -100,6 +139,23 @@ may be needed:
;; otherwise fail.
@end lisp
The other possibility is to use the @code{--use-srfi} command line
option when invoking Guile (@pxref{Invoking Guile}). When you do that,
the specified SRFI support modules will be loaded and add their feature
identifier to the list of symbols checked by @code{cond-expand}.
So, if you invoke Guile like this:
@example
$ guile --use-srfi=8
@end example
the following snippet will expand to @code{'hooray}.
@lisp
(cond-expand (srfi-8 'hooray))
@end lisp
@node SRFI-2
@section SRFI-2 - and-let*
@ -154,7 +210,7 @@ procedures easier. It is documented in @xref{Multiple Values}.
This is the SRFI way for defining record types. The Guile
implementation is a layer above Guile's normal record construction
procedures (REFFIXME). The nice thing about this kind of record
procedures (@pxref{Records}). The nice thing about this kind of record
definition method is that no new names are implicitly created, all
constructor, accessor and predicates are explicitly given. This reduces
the risk of variable capture.
@ -242,8 +298,8 @@ read in. The result of @var{proc} is returned by the Scheme reader.
This module implements the binding forms for multiple values
@code{let-values} and @code{let-values*}. These forms are similar to
@code{let} and @code{let*} (REFFIXME), but they support binding of the
values returned by multiple-valued expressions.
@code{let} and @code{let*} (@pxref{Local Bindings}), but they support
binding of the values returned by multiple-valued expressions.
Write @code{(use-modules (srfi srfi-11))} to make the bindings
available.
@ -272,7 +328,8 @@ In this section, we will describe all procedures defined in SRFI-13
Note that only the procedures from SRFI-13 are documented here which are
not already contained in Guile. For procedures not documented here
please refer to the relevant chapters in the Guile Reference Manual, for
example the documentation of strings and string procedures (REFFIXME).
example the documentation of strings and string procedures
(@pxref{Strings}).
All of the procedures defined in SRFI-13, which are not already included
in the Guile core library, are implemented in the module @code{(srfi
@ -387,7 +444,8 @@ produce the corresponding string element. The order in which
The procedure @code{string->list} is extended by SRFI-13, that is why it
is included in @code{(srfi srfi-13)}. The other procedures are new.
The Guile core already contains the procedure @code{list->string} for
converting a list of characters into a string (REFFIXME).
converting a list of characters into a string (@pxref{List/String
Conversion}).
@deffn primitive string->list str [start end]
Convert the string @var{str} into a list of characters.
@ -436,7 +494,8 @@ These procedures are called @dfn{selectors}, because they access
information about the string or select pieces of a given string.
Additional selector procedures are documented in the Strings section
(REFFIXME), like @code{string-length} or @code{string-ref}.
(@pxref{String Selection}), like @code{string-length} or
@code{string-ref}.
@code{string-copy} is also available in core Guile, but this version
accepts additional start/end indices.
@ -512,7 +571,8 @@ trimmed.
The procedure @code{string-fill!} is extended from R5RS because it
accepts optional start/end indices. This bindings shadows the procedure
of the same name in the Guile core. The second modification procedure
@code{string-set!} is documented in the Strings section (REFFIXME).
@code{string-set!} is documented in the Strings section (@pxref{String
Modification}).
@deffn primitive string-fill! str chr [start end]
Stores @var{chr} in every element of the given @var{str} and
@ -943,9 +1003,10 @@ guile>
@node SRFI-14 Character Set Data Type
@subsection Character Set Data Type
The data type @dfn{charset} implements sets of characters (REFFIXME).
Because the internal representation of character sets is not visible to
the user, a lot of procedures for handling them are provided.
The data type @dfn{charset} implements sets of characters
(@pxref{Characters}). Because the internal representation of character
sets is not visible to the user, a lot of procedures for handling them
are provided.
Character sets can be created, extended, tested for the membership of a
characters and be compared to other character sets.
@ -1327,8 +1388,8 @@ EBNF grammar.
The value returned by a @code{case-lambda} form is a procedure which
matches the number of actual arguments against the formals in the
various clauses, in order. @dfn{Formals} means a formal argument list
just like with @code{lambda} (REFFIXME). The first matching clause is
selected, the corresponding values from the actual parameter list are
just like with @code{lambda} (@pxref{Lambda}). The first matching clause
is selected, the corresponding values from the actual parameter list are
bound to the variable names in the clauses and the body of the clause is
evaluated. If no clause matches, an error is signalled.
@ -1382,3 +1443,4 @@ the setter of a procedure. In fact, @code{(set! (setter @var{proc})
procedure is to create a new object (a @dfn{procedure with setter}) via
the @code{getter-with-setter} procedure. This procedure is also
specified in the SRFI. Using it avoids the described problems.