Skip test for changing TZ if running in a pseudo-fork (on Win32)

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

diff --git a/pod/perlre.pod b/pod/perlre.pod
index 015881b..a076d3a 100644 (file)
--- a/pod/perlre.pod
+++ b/pod/perlre.pod
@@ -102,7 +102,7 @@ X</x>
 
 =head3 Metacharacters
 
-The patterns used in Perl pattern matching evolved from the ones supplied in
+The patterns used in Perl pattern matching evolved from those supplied in
 the Version 8 regex routines.  (The routines are derived
 (distantly) from Henry Spencer's freely redistributable reimplementation
 of the V8 routines.)  See L<Version 8 Regular Expressions> for
@@ -258,7 +258,7 @@ X<word> X<whitespace> X<character class> X<backreference>
     \pP             Match P, named property.  Use \p{Prop} for longer names.
     \PP             Match non-P
     \X      Match eXtended Unicode "combining character sequence",
-             equivalent to (?:\PM\pM*)
+             equivalent to (?>\PM\pM*)
     \C      Match a single C char (octet) even under Unicode.
             NOTE: breaks up characters into their UTF-8 bytes,
             so you may end up with malformed pieces of UTF-8.
@@ -375,20 +375,60 @@ X<character class> X<\p> X<\p{}>
     digit       IsDigit        \d
     graph       IsGraph
     lower       IsLower
-    print       IsPrint
-    punct       IsPunct
+    print       IsPrint                (but see [2] below)
+    punct       IsPunct                (but see [3] below)
     space       IsSpace
                 IsSpacePerl    \s
     upper       IsUpper
-    word        IsWord
+    word        IsWord         \w
     xdigit      IsXDigit
 
 For example C<[[:lower:]]> and C<\p{IsLower}> are equivalent.
 
+However, the equivalence between C<[[:xxxxx:]]> and C<\p{IsXxxxx}>
+is not exact.
+
+=over 4
+
+=item [1]
+
 If the C<utf8> pragma is not used but the C<locale> pragma is, the
 classes correlate with the usual isalpha(3) interface (except for
 "word" and "blank").
 
+But if the C<locale> or C<encoding> pragmas are not used and
+the string is not C<utf8>, then C<[[:xxxxx:]]> (and C<\w>, etc.)
+will not match characters 0x80-0xff; whereas C<\p{IsXxxxx}> will
+force the string to C<utf8> and can match these characters
+(as Unicode).
+
+=item [2]
+
+C<\p{IsPrint}> matches characters 0x09-0x0d but C<[[:print:]]> does not.
+
+=item [3]
+
+C<[[:punct::]]> matches the following but C<\p{IsPunct}> does not,
+because they are classed as symbols (not punctuation) in Unicode.
+
+=over 4
+
+=item C<$>
+
+Currency symbol
+
+=item C<+> C<< < >> C<=> C<< > >> C<|> C<~>
+
+Mathematical symbols
+
+=item C<^> C<`>
+
+Modifier symbols (accents)
+
+=back
+
+=back
+
 The other named classes are:
 
 =over 4