diff options
Diffstat (limited to 'pod/perltrap.pod')
| -rw-r--r-- | pod/perltrap.pod | 42 |
1 files changed, 24 insertions, 18 deletions
diff --git a/pod/perltrap.pod b/pod/perltrap.pod index 50987cb102..f278fa0929 100644 --- a/pod/perltrap.pod +++ b/pod/perltrap.pod @@ -585,24 +585,6 @@ number of elements in the resulting list. # perl4 prints: second new # perl5 prints: 3 -=item * Discontinuance - -In Perl 4 (and versions of Perl 5 before 5.004), C<'\r'> characters in -Perl code were silently allowed, although they could cause (mysterious!) -failures in certain constructs, particularly here documents. Now, -C<'\r'> characters cause an immediate fatal error. (Note: In this -example, the notation B<\015> represents the incorrect line -ending. Depending upon your text viewer, it will look different.) - - print "foo";\015 - print "bar"; - - # perl4 prints: foobar - # perl5.003 prints: foobar - # perl5.004 dies: Illegal character \015 (carriage return) - -See L<perldiag> for full details. - =item * Deprecation Some error messages will be different. @@ -715,6 +697,30 @@ Logical tests now return an null, instead of 0 Also see L<"General Regular Expression Traps using s///, etc."> for another example of this new feature... +=item * Bitwise string ops + +When bitwise operators which can operate upon either numbers or +strings (C<& | ^ ~>) are given only strings as arguments, perl4 would +treat the operands as bitstrings so long as the program contained a call +to the C<vec()> function. perl5 treats the string operands as bitstrings. +(See L<perlop/Bitwise String Operators> for more details.) + + $fred = "10"; + $barney = "12"; + $betty = $fred & $barney; + print "$betty\n"; + # Uncomment the next line to change perl4's behavior + # ($dummy) = vec("dummy", 0, 0); + + # Perl4 prints: + 8 + + # Perl5 prints: + 10 + + # If vec() is used anywhere in the program, both print: + 10 + =back =head2 General data type traps |