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-rw-r--r--doc/ref/api-macros.texi72
1 files changed, 36 insertions, 36 deletions
diff --git a/doc/ref/api-macros.texi b/doc/ref/api-macros.texi
index 7ff5bf9bc..e60864ba3 100644
--- a/doc/ref/api-macros.texi
+++ b/doc/ref/api-macros.texi
@@ -1,6 +1,6 @@
@c -*-texinfo-*-
@c This is part of the GNU Guile Reference Manual.
-@c Copyright (C) 1996, 1997, 2000, 2001, 2002, 2003, 2004, 2009, 2010, 2011
+@c Copyright (C) 1996, 1997, 2000, 2001, 2002, 2003, 2004, 2009, 2010, 2011, 2012
@c Free Software Foundation, Inc.
@c See the file guile.texi for copying conditions.
@@ -865,31 +865,32 @@ wrapping in @code{#'} syntax forms.
@node Syntax Parameters
@subsection Syntax Parameters
-Syntax parameters@footnote{Described in the paper @cite{Keeping it Clean with
-Syntax Parameters} by Barzilay, Culpepper and Flatt.} are a mechanism for rebinding a macro
-definition within the dynamic extent of a macro expansion. It provides
-a convenient solution to one of the most common types of unhygienic
-macro: those that introduce a unhygienic binding each time the macro
-is used. Examples include a @code{lambda} form with a @code{return} keyword, or
-class macros that introduce a special @code{self} binding.
+Syntax parameters@footnote{Described in the paper @cite{Keeping it Clean
+with Syntax Parameters} by Barzilay, Culpepper and Flatt.} are a
+mechanism for rebinding a macro definition within the dynamic extent of
+a macro expansion. This provides a convenient solution to one of the
+most common types of unhygienic macro: those that introduce a unhygienic
+binding each time the macro is used. Examples include a @code{lambda}
+form with a @code{return} keyword, or class macros that introduce a
+special @code{self} binding.
With syntax parameters, instead of introducing the binding
-unhygienically each time, we instead create one binding for the
-keyword, which we can then adjust later when we want the keyword to
-have a different meaning. As no new bindings are introduced, hygiene
-is preserved. This is similar to the dynamic binding mechanisms we
-have at run-time like @ref{SRFI-39, parameters} or
-@ref{Fluids and Dynamic States, fluids}, except that the dynamic
-binding only occurs during macro expansion. The code after macro
-expansion remains lexically scoped.
+unhygienically each time, we instead create one binding for the keyword,
+which we can then adjust later when we want the keyword to have a
+different meaning. As no new bindings are introduced, hygiene is
+preserved. This is similar to the dynamic binding mechanisms we have at
+run-time (@pxref{SRFI-39, parameters}), except that the dynamic binding
+only occurs during macro expansion. The code after macro expansion
+remains lexically scoped.
@deffn {Syntax} define-syntax-parameter keyword transformer
-Binds @var{keyword} to the value obtained by evaluating @var{transformer}. The
-@var{transformer} provides the default expansion for the syntax parameter,
-and in the absence of @code{syntax-parameterize}, is functionally equivalent
-to @code{define-syntax}. Usually, you will just want to have the @var{transformer}
-throw a syntax error indicating that the @var{keyword} is supposed to be
-used in conjunction with another macro, for example:
+Binds @var{keyword} to the value obtained by evaluating
+@var{transformer}. The @var{transformer} provides the default expansion
+for the syntax parameter, and in the absence of
+@code{syntax-parameterize}, is functionally equivalent to
+@code{define-syntax}. Usually, you will just want to have the
+@var{transformer} throw a syntax error indicating that the @var{keyword}
+is supposed to be used in conjunction with another macro, for example:
@example
(define-syntax-parameter return
(lambda (stx)
@@ -899,31 +900,30 @@ used in conjunction with another macro, for example:
@deffn {Syntax} syntax-parameterize ((keyword transformer) @dots{}) exp @dots{}
Adjusts @var{keyword} @dots{} to use the values obtained by evaluating
-their @var{transformer} @dots{}, in the expansion of the @var{exp} @dots{}
-forms. Each @var{keyword} must be bound to a
-syntax-parameter. @code{syntax-parameterize} differs from
-@code{let-syntax}, in that the binding is not shadowed, but adjusted,
-and so uses of the keyword in the expansion of exp forms use the new
-transformers. This is somewhatsimilar to how @code{parameterize}
-adjusts the values of regular parameters, rather than creating new
-bindings.
+their @var{transformer} @dots{}, in the expansion of the @var{exp}
+@dots{} forms. Each @var{keyword} must be bound to a syntax-parameter.
+@code{syntax-parameterize} differs from @code{let-syntax}, in that the
+binding is not shadowed, but adjusted, and so uses of the keyword in the
+expansion of @var{exp} @dots{} use the new transformers. This is
+somewhat similar to how @code{parameterize} adjusts the values of
+regular parameters, rather than creating new bindings.
@example
(define-syntax lambda^
(syntax-rules ()
- [(lambda^ argument-list body bodies ...)
+ [(lambda^ argument-list body body* ...)
(lambda argument-list
(call-with-current-continuation
(lambda (escape)
- ;; in the body we adjust the 'return' keyword so that calls
- ;; to 'return' are replaced with calls to the escape continuation
+ ;; In the body we adjust the 'return' keyword so that calls
+ ;; to 'return' are replaced with calls to the escape
+ ;; continuation.
(syntax-parameterize ([return (syntax-rules ()
[(return vals (... ...))
(escape vals (... ...))])])
- body
- bodies ...))))]))
+ body body* ...))))]))
-;; now we can write functions that return early. Here, 'product' will
+;; Now we can write functions that return early. Here, 'product' will
;; return immediately if it sees any 0 element.
(define product
(lambda^ (list)