more uni doc tweakage

[perl5.git] / pod / perldata.pod

diff --git a/pod/perldata.pod b/pod/perldata.pod
index f60d016..5ff97d4 100644 (file)
--- a/pod/perldata.pod
+++ b/pod/perldata.pod
@@ -341,6 +341,11 @@ an expression.
 
 =head3 Version Strings
 
+B<Note:> Version Strings (v-strings) have been deprecated.  They will
+be removed in some future release after Perl 5.8.1.  The marginal
+benefits of v-strings were greatly outweighed by the potential for
+Surprise and Confusion.
+
 A literal of the form C<v1.20.300.4000> is parsed as a string composed
 of characters with the specified ordinals.  This form, known as
 v-strings, provides an alternative, more readable way to construct
@@ -360,6 +365,14 @@ running Perl interpreter's version in this form.  See L<perlvar/$^V>.
 Note that using the v-strings for IPv4 addresses is not portable unless
 you also use the inet_aton()/inet_ntoa() routines of the Socket package.
 
+Note that since Perl 5.8.1 the single-number v-strings (like C<v65>)
+are not v-strings before the C<< => >> operator (which is usually used
+to separate a hash key from a hash value), instead they are interpreted
+as literal strings ('v65').  They were v-strings from Perl 5.6.0 to
+Perl 5.8.0, but that caused more confusion and breakage than good.
+Multi-number v-strings like C<v65.66> and C<65.66.67> continue to
+be v-strings always.
+
 =head3 Special Literals
 
 The special literals __FILE__, __LINE__, and __PACKAGE__
@@ -587,8 +600,9 @@ key/value pairs.  That's why it's good to use references sometimes.
 It is often more readable to use the C<< => >> operator between key/value
 pairs.  The C<< => >> operator is mostly just a more visually distinctive
 synonym for a comma, but it also arranges for its left-hand operand to be
-interpreted as a string--if it's a bareword that would be a legal identifier.
-This makes it nice for initializing hashes:
+interpreted as a string -- if it's a bareword that would be a legal simple
+identifier (C<< => >> doesn't quote compound identifiers, that contain
+double colons). This makes it nice for initializing hashes:
 
     %map = (
                  red   => 0x00f,