consting for .c files in tests

[perl5.git] / pod / perlsub.pod

diff --git a/pod/perlsub.pod b/pod/perlsub.pod
index f11f1ae..72b28f1 100644 (file)
--- a/pod/perlsub.pod
+++ b/pod/perlsub.pod
@@ -453,26 +453,10 @@ each time the gimme_another() function is called:
 Also, since C<$x> is lexical, it can't be reached or modified by any Perl
 code outside.
 
-You can initialize state variables, and the assigment will be executed
-only once:
-
-    sub starts_from_42 { state $x = 42; return ++$x }
-
-You can also, as a syntactic shortcut, initialize more than one if they're
-all declared within the same state() clause:
-
-    state ($a, $b, $c) = ( 'one', 'two', 'three' );
-
-However, be warned that state variables declared as part of a list will
-get assigned each time the statement will be executed, since it will be
-considered as a regular list assigment, not one to be executed only once:
-
-    (state $x, my $y) = (1, 2); # $x gets reinitialized every time !
-
-B<Caveat>: the code at the right side of the assignment to a state
-variable will be executed every time; only the assignment is disabled. So,
-avoid code that has side-effects, or that is slow to execute. This might
-be optimized out in a future version of Perl.
+When combined with variable declaration, simple scalar assignment to C<state>
+variables (as in C<state $x = 42>) is executed only the first time.  When such
+statements are evaluated subsequent times, the assignment is ignored.  The
+behavior of this sort of assignment to non-scalar variables is undefined.
 
 =head3 Persistent variables with closures
 
@@ -1317,10 +1301,9 @@ that understands regular expressions.
     sub glob {
        my $pat = shift;
        my @got;
-       local *D;
-       if (opendir D, '.') { 
-           @got = grep /$pat/, readdir D; 
-           closedir D;   
+       if (opendir my $d, '.') { 
+           @got = grep /$pat/, readdir $d; 
+           closedir $d;   
        }
        return @got;
     }
@@ -1372,7 +1355,8 @@ And, as you'll have noticed from the previous example, if you override
 C<glob>, the C<< <*> >> glob operator is overridden as well.
 
 In a similar fashion, overriding the C<readline> function also overrides
-the equivalent I/O operator C<< <FILEHANDLE> >>.
+the equivalent I/O operator C<< <FILEHANDLE> >>. Also, overriding
+C<readpipe> also overrides the operators C<``> and C<qx//>.
 
 Finally, some built-ins (e.g. C<exists> or C<grep>) can't be overridden.