[Emacs-diffs] trunk r115729: Fix missing arg in pcase example.

[Tassilo Horn]

------------------------------------------------------------
revno: 115729
revision-id: address@hidden
parent: address@hidden
fixes bug: http://debbugs.gnu.org/16238
committer: Tassilo Horn <address@hidden>
branch nick: trunk
timestamp: Tue 2013-12-24 16:30:59 +0100
message:
  Fix missing arg in pcase example.
  
  * doc/lispref/control.texi (Pattern matching case statement): Fix missing
  argument in simple expression language sample.  Add
  some sample programs written in that language.  Mention that
  `pcase' requires lexical binding.
modified:
  doc/lispref/ChangeLog          changelog-20091113204419-o5vbwnq5f7feedwu-6155
  doc/lispref/control.texi       
control.texi-20091113204419-o5vbwnq5f7feedwu-6169

=== modified file 'doc/lispref/ChangeLog'
--- a/doc/lispref/ChangeLog     2013-12-23 11:27:29 +0000
+++ b/doc/lispref/ChangeLog     2013-12-24 15:30:59 +0000
@@ -1,3 +1,10 @@
+2013-12-24  Tassilo Horn  <address@hidden>
+
+       * control.texi (Pattern matching case statement): Fix missing
+       argument in simple expression language sample (Bug#16238).  Add
+       some sample programs written in that language.  Mention that
+       `pcase' requires lexical binding.
+
 2013-12-23  Xue Fuqiao  <address@hidden>
 
        * eval.texi (Special Forms): Document `special-form-p'.

=== modified file 'doc/lispref/control.texi'
--- a/doc/lispref/control.texi  2013-10-09 17:17:20 +0000
+++ b/doc/lispref/control.texi  2013-12-24 15:30:59 +0000
@@ -328,7 +328,7 @@
 (defun evaluate (exp env)
   (pcase exp
     (`(add ,x ,y)         (+ (evaluate x env) (evaluate y env)))
-    (`(call ,fun ,arg)    (funcall (evaluate fun) (evaluate arg env)))
+    (`(call ,fun ,arg)    (funcall (evaluate fun env) (evaluate arg env)))
     (`(fn ,arg ,body)     (lambda (val)
                             (evaluate body (cons (cons arg val) env))))
     ((pred numberp)       exp)
@@ -342,6 +342,19 @@
 @code{(pred numberp)} is a pattern that simply checks that @code{exp}
 is a number, and @code{_} is the catch-all pattern that matches anything.
 
+Here are some sample programs including their evaluation results:
+
address@hidden
+(evaluate '(add 1 2) nil)                 ;=> 3
+(evaluate '(add x y) '((x . 1) (y . 2)))  ;=> 3
+(evaluate '(call (fn x (add 1 x)) 2) nil) ;=> 3
+(evaluate '(sub 1 2) nil)                 ;=> (error "Unknown expression (sub 
1 2)")
address@hidden example
+
+Note that (parts of) @code{pcase} only work as expected with lexical
+binding, so lisp files using @code{pcase} should have enable it
+(@pxref{Using Lexical Binding}, for how to enable lexical binding).
+
 There are two kinds of patterns involved in @code{pcase}, called
 @emph{U-patterns} and @emph{Q-patterns}.  The @var{upattern} mentioned above
 are U-patterns and can take the following forms: