Make using U+FDD0..U+FDEF (noncharacters since Unicode 3.1),

[p5sagit/p5-mst-13.2.git] / pod / perlsyn.pod

diff --git a/pod/perlsyn.pod b/pod/perlsyn.pod
index 6d820b6..9d0c920 100644 (file)
--- a/pod/perlsyn.pod
+++ b/pod/perlsyn.pod
@@ -263,7 +263,7 @@ available.   Replace any occurrence of C<if BLOCK> by C<if (do BLOCK)>.
 
 =head2 For Loops
 
-Perl's C-style C<for> loop works exactly like the corresponding C<while> loop;
+Perl's C-style C<for> loop works like the corresponding C<while> loop;
 that means that this:
 
     for ($i = 1; $i < 10; $i++) {
@@ -279,8 +279,10 @@ is the same as this:
        $i++;
     }
 
-(There is one minor difference: The first form implies a lexical scope
-for variables declared with C<my> in the initialization expression.)
+There is one minor difference: if variables are declared with C<my>
+in the initialization section of the C<for>, the lexical scope of
+those variables is exactly the C<for> loop (the body of the loop
+and the control sections).
 
 Besides the normal array index looping, C<for> can lend itself
 to many other interesting applications.  Here's one that avoids the
@@ -309,9 +311,12 @@ The C<foreach> keyword is actually a synonym for the C<for> keyword, so
 you can use C<foreach> for readability or C<for> for brevity.  (Or because
 the Bourne shell is more familiar to you than I<csh>, so writing C<for>
 comes more naturally.)  If VAR is omitted, C<$_> is set to each value.
-If any element of LIST is an lvalue, you can modify it by modifying VAR
-inside the loop.  That's because the C<foreach> loop index variable is
-an implicit alias for each item in the list that you're looping over.
+
+If any element of LIST is an lvalue, you can modify it by modifying
+VAR inside the loop.  Conversely, if any element of LIST is NOT an
+lvalue, any attempt to modify that element will fail.  In other words,
+the C<foreach> loop index variable is an implicit alias for each item
+in the list that you're looping over.
 
 If any part of LIST is an array, C<foreach> will get very confused if
 you add or remove elements within the loop body, for example with
@@ -388,8 +393,18 @@ structures.
     }
 
 There is no official C<switch> statement in Perl, because there are
-already several ways to write the equivalent.  In addition to the
-above, you could write
+already several ways to write the equivalent.
+
+However, starting from Perl 5.8 to get switch and case one can use
+the Switch extension and say:
+
+       use Switch;
+
+after which one has switch and case.  It is not as fast as it could be
+because it's not really part of the language (it's done using source
+filters) but it is available, and it's very flexible.
+
+In addition to the above BLOCK construct, you could write
 
     SWITCH: {
        $abc = 1, last SWITCH  if /^abc/;