diff options
Diffstat (limited to 'pod/perlreapi.pod')
| -rw-r--r-- | pod/perlreapi.pod | 38 |
1 files changed, 21 insertions, 17 deletions
diff --git a/pod/perlreapi.pod b/pod/perlreapi.pod index 3b5dc852fd..084762dd94 100644 --- a/pod/perlreapi.pod +++ b/pod/perlreapi.pod @@ -124,20 +124,6 @@ Additional flags: =over 4 -=item RXf_SKIPWHITE - -If C<split> is invoked as C<split ' '> or with no arguments (which -really means C<split(' ', $_>, see L<split|perlfunc/split>), perl will set -this flag and change the pattern from C<" "> to C<"\s+"> before it's -passed to the comp routine. - -If the flag is present in C<< rx->extflags >> C<split> to delete -whitespace from the start of the subject string before it's operated -on. What is considered whitespace depends on whether the subject is a -UTF-8 string and whether the C<RXf_PMf_LOCALE> flag is set. - -This probably always be preserved verbatim in C<< rx->extflags >>. - =item RXf_PMf_LOCALE Set if C<use locale> is in effect. If present in C<< rx->extflags >> @@ -156,6 +142,16 @@ compilation. The perl engine for instance may upgrade non-UTF-8 strings to UTF-8 if the pattern includes constructs such as C<\x{...}> that can only match Unicode values. +=item RXf_SPLIT + +If C<split> is invoked as C<split ' '> or with no arguments (which +really means C<split(' ', $_>, see L<split|perlfunc/split>), perl will +set this flag. The regex engine can then check for it and set the +SKIPWHITE and WHITE extflags. To do this the perl engine does: + + if (flags & RXf_SPLIT && r->prelen == 1 && r->precomp[0] == ' ') + r->extflags |= (RXf_SKIPWHITE|RXf_WHITE); + =back These flags can be set during compilation to enable optimizations in @@ -163,6 +159,16 @@ the C<split> operator. =over 4 +=item RXf_SKIPWHITE + +If the flag is present in C<< rx->extflags >> C<split> will delete +whitespace from the start of the subject string before it's operated +on. What is considered whitespace depends on whether the subject is a +UTF-8 string and whether the C<RXf_PMf_LOCALE> flag is set. + +If RXf_WHITE is set in addition to this flag C<split> will behave like +C<split " "> under the perl engine. + =item RXf_START_ONLY Tells the split operator to split the target string on newlines @@ -180,9 +186,7 @@ without invoking the regex engine. The definition of whitespace varies depending on whether the target string is a UTF-8 string and on whether RXf_PMf_LOCALE is set. -Perl's engine sets this flag if the pattern is C<\s+>, which it will be if -the pattern actually was C<\s+> or if it was originally C<" "> (see -C<RXf_SKIPWHITE> above). +Perl's engine sets this flag if the pattern is C<\s+>. =back |