scratch/lisp-func-type-decls 15016288eca 4/4: * Document function type declarations

[Andrea Corallo]

branch: scratch/lisp-func-type-decls
commit 15016288ecaefbfb2822c1fcef7146a5d8663650
Author: Andrea Corallo <acorallo@gnu.org>
Commit: Andrea Corallo <acorallo@gnu.org>

    * Document function type declarations
    
    * doc/lispref/functions.texi (Declare Form): Document function type
    declaration.
---
 doc/lispref/functions.texi | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/doc/lispref/functions.texi b/doc/lispref/functions.texi
index c57de08460f..b5e234fa068 100644
--- a/doc/lispref/functions.texi
+++ b/doc/lispref/functions.texi
@@ -2709,6 +2709,13 @@ native code emitted for the function.  In particular, if 
@var{n} is
 @minus{}1, native compilation of the function will emit bytecode
 instead of native code for the function.
 
+@item (type @var{type})
+Declare @var{type} to be the type of this function.  This is used for
+documentation by @code{describe-function}.  Also it can be used by the
+native compiler (@pxref{Native-Compilation}) for improving code
+generation and for deriving more precisely the type of other functions
+without type declaration.
+
 @item no-font-lock-keyword
 This is valid for macros only.  Macros with this declaration are
 highlighted by font-lock (@pxref{Font Lock Mode}) as normal functions,