doc: Use @defmac and @defspec for macros.

* doc/guix.texi (package Reference, Defining Package Variants)
(Build Utilities, The Store Monad, G-Expressions, operating-system Reference)
(Service Reference, Complex Configurations): Use @defmac and @defspec for macros.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>
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Bruno Victal 2023-03-08 01:22:09 +00:00 committed by Ludovic Courtès
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@ -7781,7 +7781,7 @@ automatically corrected.
@end table
@end deftp
@deffn {Scheme Syntax} this-package
@defmac this-package
When used in the @emph{lexical scope} of a package field definition, this
identifier resolves to the package being defined.
@ -7801,7 +7801,7 @@ cross-compiling:
@end lisp
It is an error to refer to @code{this-package} outside a package definition.
@end deffn
@end defmac
The following helper procedures are provided to help deal with package
inputs.
@ -8160,7 +8160,7 @@ from the @code{inputs} field of @code{gdb}. The @code{modify-inputs}
macro is a helper that can prove useful anytime you want to remove, add,
or replace package inputs.
@deffn {Scheme Syntax} modify-inputs @var{inputs} @var{clauses}
@defmac modify-inputs inputs clauses
Modify the given package inputs, as returned by @code{package-inputs} & co.,
according to the given clauses. Each clause must have one of the
following forms:
@ -8195,7 +8195,7 @@ The example below replaces the @code{guile} package from the inputs of
The last type of clause is @code{append}, to add inputs at the back of
the list.
@end deffn
@end defmac
In some cases, you may find it useful to write functions
(``procedures'', in Scheme parlance) that return a package based on some
@ -10164,7 +10164,7 @@ such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
@command{sed}. They complement Guile's extensive, but low-level, file
system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
@deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
@defmac with-directory-excursion directory body @dots{}
Run @var{body} with @var{directory} as the process's current directory.
Essentially, this macro changes the current directory to @var{directory}
@ -10173,7 +10173,7 @@ guile, GNU Guile Reference Manual}). It changes back to the initial
directory when the dynamic extent of @var{body} is left, be it @i{via}
normal procedure return or @i{via} a non-local exit such as an
exception.
@end deffn
@end defmac
@defun mkdir-p dir
Create directory @var{dir} and all its ancestors.
@ -10205,8 +10205,8 @@ symlinks. Don't follow mount points either, unless @var{follow-mounts?}
is true. Report but ignore errors.
@end defun
@deffn {Scheme Syntax} substitute* @var{file} @
((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
@defmac substitute* file @
((regexp match-var@dots{}) body@dots{}) @dots{}
Substitute @var{regexp} in @var{file} by the string returned by
@var{body}. @var{body} is evaluated with each @var{match-var} bound to
the corresponding positional regexp sub-expression. For example:
@ -10232,7 +10232,7 @@ they are all subject to the substitutions.
Be careful about using @code{$} to match the end of a line; by itself it
won't match the terminating newline of a line.
@end deffn
@end defmac
@subsection File Search
@ -10393,7 +10393,7 @@ manipulate alists. The @code{(guix build utils)} module complements
those with tools written with build phases in mind.
@cindex build phases, modifying
@deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
@defmac modify-phases phases clause@dots{}
Modify @var{phases} sequentially as per each @var{clause}, which may
have one of the following forms:
@ -10406,7 +10406,7 @@ have one of the following forms:
Where every @var{phase-name} above is an expression evaluating to a
symbol, and @var{new-phase} an expression evaluating to a procedure.
@end deffn
@end defmac
The example below is taken from the definition of the @code{grep}
package. It adds a phase to run after the @code{install} phase, called
@ -11193,16 +11193,16 @@ build a file-like object (@pxref{Using Guix Interactively}).
The main syntactic forms to deal with monads in general are provided by
the @code{(guix monads)} module and are described below.
@deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
@defmac with-monad monad body @dots{}
Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
in @var{monad}.
@end deffn
@end defmac
@deffn {Scheme Syntax} return @var{val}
@defmac return val
Return a monadic value that encapsulates @var{val}.
@end deffn
@end defmac
@deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
@defmac >>= mval mproc @dots{}
@dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
procedures @var{mproc}@dots{}@footnote{This operation is commonly
referred to as ``bind'', but that name denotes an unrelated procedure in
@ -11221,12 +11221,10 @@ in this example:
@result{} 4
@result{} some-state
@end lisp
@end deffn
@end defmac
@deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
@var{body} ...
@deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
@var{body} ...
@defmac mlet monad ((var mval) @dots{}) body @dots{}
@defmacx mlet* monad ((var mval) @dots{}) body @dots{}
Bind the variables @var{var} to the monadic values @var{mval} in
@var{body}, which is a sequence of expressions. As with the bind
operator, this can be thought of as ``unpacking'' the raw, non-monadic
@ -11240,9 +11238,9 @@ expression, and its result will become the result of the @code{mlet} or
@code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
(@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
@end deffn
@end defmac
@deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
@defmac mbegin monad mexp @dots{}
Bind @var{mexp} and the following monadic expressions in sequence,
returning the result of the last expression. Every expression in the
sequence must be a monadic expression.
@ -11250,21 +11248,21 @@ sequence must be a monadic expression.
This is akin to @code{mlet}, except that the return values of the
monadic expressions are ignored. In that sense, it is analogous to
@code{begin}, but applied to monadic expressions.
@end deffn
@end defmac
@deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
@defmac mwhen condition mexp0 mexp* @dots{}
When @var{condition} is true, evaluate the sequence of monadic
expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
@var{condition} is false, return @code{*unspecified*} in the current
monad. Every expression in the sequence must be a monadic expression.
@end deffn
@end defmac
@deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
@defmac munless condition mexp0 mexp* @dots{}
When @var{condition} is false, evaluate the sequence of monadic
expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
@var{condition} is true, return @code{*unspecified*} in the current
monad. Every expression in the sequence must be a monadic expression.
@end deffn
@end defmac
@cindex state monad
The @code{(guix monads)} module provides the @dfn{state monad}, which
@ -11585,8 +11583,8 @@ package available on the build side, here's how you would do it:
The syntactic form to construct gexps is summarized below.
@deffn {Scheme Syntax} #~@var{exp}
@deffnx {Scheme Syntax} (gexp @var{exp})
@defmac #~@var{exp}
@defmacx (gexp @var{exp})
Return a G-expression containing @var{exp}. @var{exp} may contain one
or more of the following forms:
@ -11640,9 +11638,9 @@ Like the above, but refers to native builds of the objects listed in
G-expressions created by @code{gexp} or @code{#~} are run-time objects
of the @code{gexp?} type (see below).
@end deffn
@end defmac
@deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
@defmac with-imported-modules modules body@dots{}
Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
in their execution environment.
@ -11664,9 +11662,9 @@ path, and the last one is created from the given file-like object.
This form has @emph{lexical} scope: it has an effect on the gexps
directly defined in @var{body}@dots{}, but not on those defined, say, in
procedures called from @var{body}@dots{}.
@end deffn
@end defmac
@deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
@defmac with-extensions extensions body@dots{}
Mark the gexps defined in @var{body}@dots{} as requiring
@var{extensions} in their build and execution environment.
@var{extensions} is typically a list of package objects such as those
@ -11676,7 +11674,7 @@ Concretely, the packages listed in @var{extensions} are added to the
load path while compiling imported modules in @var{body}@dots{}; they
are also added to the load path of the gexp returned by
@var{body}@dots{}.
@end deffn
@end defmac
@defun gexp? obj
Return @code{#t} if @var{obj} is a G-expression.
@ -11960,8 +11958,8 @@ the second case, the resulting script contains a @code{(string-append
@dots{})} expression to construct the file name @emph{at run time}.
@end defun
@deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
@deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
@defmac let-system system body@dots{}
@defmacx let-system (system target) body@dots{}
Bind @var{system} to the currently targeted system---e.g.,
@code{"x86_64-linux"}---within @var{body}.
@ -11984,9 +11982,9 @@ spliced into the gexp depends on the target system, as in this example:
(error "dunno!"))))
"-net" "user" #$image)
@end lisp
@end deffn
@end defmac
@deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
@defmac with-parameters ((parameter value) @dots{}) exp
This macro is similar to the @code{parameterize} form for
dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
Guile Reference Manual}). The key difference is that it takes effect
@ -12003,7 +12001,7 @@ for a given object:
The example above returns an object that corresponds to the i686 build
of Coreutils, regardless of the current value of @code{%current-system}.
@end deffn
@end defmac
Of course, in addition to gexps embedded in ``host'' code, there are
@ -16654,7 +16652,7 @@ is that only @code{root} and members of the @code{wheel} group may use
@end table
@deffn {Scheme Syntax} this-operating-system
@defmac this-operating-system
When used in the @emph{lexical scope} of an operating system field definition,
this identifier resolves to the operating system being defined.
@ -16672,7 +16670,7 @@ the definition of the @code{label} field:
It is an error to refer to @code{this-operating-system} outside an operating
system definition.
@end deffn
@end defmac
@end deftp
@ -40595,8 +40593,8 @@ standard list combinators such as @code{map} and @code{fold} to do that
@code{modify-services} simply provides a more concise form for this
common pattern.
@deffn {Scheme Syntax} modify-services @var{services} @
(@var{type} @var{variable} => @var{body}) @dots{}
@defspec modify-services services @
(type variable => body) @dots{}
Modify the services listed in @var{services} according to the given
clauses. Each clause has the form:
@ -40629,7 +40627,7 @@ Such a clause removes all services of the given @var{type} from
@xref{Using the Configuration System}, for example usage.
@end deffn
@end defspec
Next comes the programming interface for service types. This is
something you want to know when writing new service definitions, but not
@ -41105,8 +41103,7 @@ procedures that take some kind of Scheme value and returns a
G-expression (@pxref{G-Expressions}), which should, once serialized to
the disk, return a string. More details are listed below.
@deffn {Scheme Syntax} define-configuration @var{name} @var{clause1} @
@var{clause2} ...
@defmac define-configuration name clause1 clause2 @dots{}
Create a record type named @code{@var{name}} that contains the
fields found in the clauses.
@ -41216,9 +41213,9 @@ macro which is a shorthand of this.
(string "test")
"Some documentation."))
@end lisp
@end deffn
@end defmac
@deffn {Scheme Syntax} define-maybe @var{type}
@defmac define-maybe type
Sometimes a field should not be serialized if the user doesnt specify a
value. To achieve this, you can use the @code{define-maybe} macro to
define a ``maybe type''; if the value of a maybe type is left unset, or
@ -41270,7 +41267,7 @@ whether its value is set or not.
maybe-symbol
"Docstring."))
@end lisp
@end deffn
@end defmac
@defun maybe-value-set? value
Predicate to check whether a user explicitly specified the value of a