# new features supported
}
-C<require> and C<use> also have some special magic to support such literals.
-They will be interpreted as a version rather than as a module name:
+C<require> and C<use> also have some special magic to support such
+literals, but this particular usage should be avoided because it leads to
+misleading error messages under versions of Perl which don't support vector
+strings. Using a true version number will ensure correct behavior in all
+versions of Perl:
- require v5.6.0; # croak if $^V lt v5.6.0
- use v5.6.0; # same, but croaks at compile-time
-
-Alternatively, the C<v> may be omitted if there is more than one dot:
-
- require 5.6.0;
- use 5.6.0;
+ require 5.006; # run time check for v5.6
+ use 5.006_001; # compile time check for v5.6.1
Also, C<sprintf> and C<printf> support the Perl-specific format flag C<%v>
to print ordinals of characters in arbitrary strings:
already. The fatal error has been downgraded to an optional warning:
Possible unintended interpolation of @example in string
-
+
This warns you that C<"fred@example.com"> is going to turn into
C<fred.com> if you don't backslash the C<@>.
-
-See L<http://www.plover.com/~mjd/perl/at-error.html|http://www.plover.com/~mjd/perl/at-error.html>
-for more details about the history here.
+See http://www.plover.com/~mjd/perl/at-error.html for more details
+about the history here.
=head1 Modules and Pragmata
behavior, END blocks are not executed anymore when the C<-c> switch
is used, or if compilation fails.
-See L<CHECK blocks> for how to run things when the compile phase ends.
+See L</"Support for CHECK blocks"> for how to run things when the compile
+phase ends.
=head2 Potential to leak DATA filehandles
In Perl 5.6.0 and later, C<"$$1"> always means C<"${$1}">.
-=item delete(), values() and C<\(%h)> operate on aliases to values, not copies
+=item delete(), each(), values() and C<\(%h)>
-delete(), each(), values() and hashes in a list context return the actual
+operate on aliases to values, not copies
+
+delete(), each(), values() and hashes (e.g. C<\(%h)>)
+in a list context return the actual
values in the hash, instead of copies (as they used to in earlier
versions). Typical idioms for using these constructs copy the
returned values, but this can make a significant difference when
=head2 Compatible C Source API Changes
-=over
+=over 4
=item C<PATCHLEVEL> is now C<PERL_VERSION>
=item The DB module
-=item The regular expression constructs C<(?{ code })> and C<(??{ code })>
+=item The regular expression code constructs:
+
+C<(?{ code })> and C<(??{ code })>
=back