* symbols.texi (Standard Properties): Document pure. (Bug#13823)

2 files changed, 7 insertions, 2 deletions

diff --git a/doc/lispref/ChangeLog b/doc/lispref/ChangeLog
index 7455881518a..1435f24202d 100644
--- a/doc/lispref/ChangeLog
+++ b/doc/lispref/ChangeLog
@@ -1,3 +1,7 @@
+2013-03-17  Christopher Schmidt  <christopher@ch.ristopher.com>
+
+        * symbols.texi (Standard Properties): Document pure.  (Bug#13823)
+
 2013-03-16  Glenn Morris  <rgm@gnu.org>
 
         * elisp.texi: Add some stuff specific to www.gnu.org.
diff --git a/doc/lispref/symbols.texi b/doc/lispref/symbols.texi
index 9f916549902..82dfa0f4917 100644
--- a/doc/lispref/symbols.texi
+++ b/doc/lispref/symbols.texi
@@ -539,8 +539,9 @@ deleted from the local value of a hook variable when changing major
 modes.  @xref{Setting Hooks}.
 
 @item pure
-This property is used internally to mark certain named functions for
-byte compiler optimization.  Do not set it.
+If the value is non-@code{nil}, the named function is considered to be
+side-effect free.  Calls with constant arguments can be evaluated at
+compile time.  This may shift run time errors to compile time.
 
 @item risky-local-variable
 If the value is non-@code{nil}, the named variable is considered risky