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diff --git a/chromium/third_party/cygwin/lib/perl5/5.10/pods/perlreref.pod b/chromium/third_party/cygwin/lib/perl5/5.10/pods/perlreref.pod deleted file mode 100644 index b9fb3b02026..00000000000 --- a/chromium/third_party/cygwin/lib/perl5/5.10/pods/perlreref.pod +++ /dev/null @@ -1,364 +0,0 @@ -=head1 NAME - -perlreref - Perl Regular Expressions Reference - -=head1 DESCRIPTION - -This is a quick reference to Perl's regular expressions. -For full information see L<perlre> and L<perlop>, as well -as the L</"SEE ALSO"> section in this document. - -=head2 OPERATORS - -C<=~> determines to which variable the regex is applied. -In its absence, $_ is used. - - $var =~ /foo/; - -C<!~> determines to which variable the regex is applied, -and negates the result of the match; it returns -false if the match succeeds, and true if it fails. - - $var !~ /foo/; - -C<m/pattern/msixpogc> searches a string for a pattern match, -applying the given options. - - m Multiline mode - ^ and $ match internal lines - s match as a Single line - . matches \n - i case-Insensitive - x eXtended legibility - free whitespace and comments - p Preserve a copy of the matched string - - ${^PREMATCH}, ${^MATCH}, ${^POSTMATCH} will be defined. - o compile pattern Once - g Global - all occurrences - c don't reset pos on failed matches when using /g - -If 'pattern' is an empty string, the last I<successfully> matched -regex is used. Delimiters other than '/' may be used for both this -operator and the following ones. The leading C<m> can be omitted -if the delimiter is '/'. - -C<qr/pattern/msixpo> lets you store a regex in a variable, -or pass one around. Modifiers as for C<m//>, and are stored -within the regex. - -C<s/pattern/replacement/msixpogce> substitutes matches of -'pattern' with 'replacement'. Modifiers as for C<m//>, -with one addition: - - e Evaluate 'replacement' as an expression - -'e' may be specified multiple times. 'replacement' is interpreted -as a double quoted string unless a single-quote (C<'>) is the delimiter. - -C<?pattern?> is like C<m/pattern/> but matches only once. No alternate -delimiters can be used. Must be reset with reset(). - -=head2 SYNTAX - - \ Escapes the character immediately following it - . Matches any single character except a newline (unless /s is used) - ^ Matches at the beginning of the string (or line, if /m is used) - $ Matches at the end of the string (or line, if /m is used) - * Matches the preceding element 0 or more times - + Matches the preceding element 1 or more times - ? Matches the preceding element 0 or 1 times - {...} Specifies a range of occurrences for the element preceding it - [...] Matches any one of the characters contained within the brackets - (...) Groups subexpressions for capturing to $1, $2... - (?:...) Groups subexpressions without capturing (cluster) - | Matches either the subexpression preceding or following it - \1, \2, \3 ... Matches the text from the Nth group - \g1 or \g{1}, \g2 ... Matches the text from the Nth group - \g-1 or \g{-1}, \g-2 ... Matches the text from the Nth previous group - \g{name} Named backreference - \k<name> Named backreference - \k'name' Named backreference - (?P=name) Named backreference (python syntax) - -=head2 ESCAPE SEQUENCES - -These work as in normal strings. - - \a Alarm (beep) - \e Escape - \f Formfeed - \n Newline - \r Carriage return - \t Tab - \037 Any octal ASCII value - \x7f Any hexadecimal ASCII value - \x{263a} A wide hexadecimal value - \cx Control-x - \N{name} A named character - - \l Lowercase next character - \u Titlecase next character - \L Lowercase until \E - \U Uppercase until \E - \Q Disable pattern metacharacters until \E - \E End modification - -For Titlecase, see L</Titlecase>. - -This one works differently from normal strings: - - \b An assertion, not backspace, except in a character class - -=head2 CHARACTER CLASSES - - [amy] Match 'a', 'm' or 'y' - [f-j] Dash specifies "range" - [f-j-] Dash escaped or at start or end means 'dash' - [^f-j] Caret indicates "match any character _except_ these" - -The following sequences work within or without a character class. -The first six are locale aware, all are Unicode aware. See L<perllocale> -and L<perlunicode> for details. - - \d A digit - \D A nondigit - \w A word character - \W A non-word character - \s A whitespace character - \S A non-whitespace character - \h An horizontal white space - \H A non horizontal white space - \v A vertical white space - \V A non vertical white space - \R A generic newline (?>\v|\x0D\x0A) - - \C Match a byte (with Unicode, '.' matches a character) - \pP Match P-named (Unicode) property - \p{...} Match Unicode property with long name - \PP Match non-P - \P{...} Match lack of Unicode property with long name - \X Match extended Unicode combining character sequence - -POSIX character classes and their Unicode and Perl equivalents: - - alnum IsAlnum Alphanumeric - alpha IsAlpha Alphabetic - ascii IsASCII Any ASCII char - blank IsSpace [ \t] Horizontal whitespace (GNU extension) - cntrl IsCntrl Control characters - digit IsDigit \d Digits - graph IsGraph Alphanumeric and punctuation - lower IsLower Lowercase chars (locale and Unicode aware) - print IsPrint Alphanumeric, punct, and space - punct IsPunct Punctuation - space IsSpace [\s\ck] Whitespace - IsSpacePerl \s Perl's whitespace definition - upper IsUpper Uppercase chars (locale and Unicode aware) - word IsWord \w Alphanumeric plus _ (Perl extension) - xdigit IsXDigit [0-9A-Fa-f] Hexadecimal digit - -Within a character class: - - POSIX traditional Unicode - [:digit:] \d \p{IsDigit} - [:^digit:] \D \P{IsDigit} - -=head2 ANCHORS - -All are zero-width assertions. - - ^ Match string start (or line, if /m is used) - $ Match string end (or line, if /m is used) or before newline - \b Match word boundary (between \w and \W) - \B Match except at word boundary (between \w and \w or \W and \W) - \A Match string start (regardless of /m) - \Z Match string end (before optional newline) - \z Match absolute string end - \G Match where previous m//g left off - - \K Keep the stuff left of the \K, don't include it in $& - -=head2 QUANTIFIERS - -Quantifiers are greedy by default -- match the B<longest> leftmost. - - Maximal Minimal Possessive Allowed range - ------- ------- ---------- ------------- - {n,m} {n,m}? {n,m}+ Must occur at least n times - but no more than m times - {n,} {n,}? {n,}+ Must occur at least n times - {n} {n}? {n}+ Must occur exactly n times - * *? *+ 0 or more times (same as {0,}) - + +? ++ 1 or more times (same as {1,}) - ? ?? ?+ 0 or 1 time (same as {0,1}) - -The possessive forms (new in Perl 5.10) prevent backtracking: what gets -matched by a pattern with a possessive quantifier will not be backtracked -into, even if that causes the whole match to fail. - -There is no quantifier {,n} -- that gets understood as a literal string. - -=head2 EXTENDED CONSTRUCTS - - (?#text) A comment - (?:...) Groups subexpressions without capturing (cluster) - (?pimsx-imsx:...) Enable/disable option (as per m// modifiers) - (?=...) Zero-width positive lookahead assertion - (?!...) Zero-width negative lookahead assertion - (?<=...) Zero-width positive lookbehind assertion - (?<!...) Zero-width negative lookbehind assertion - (?>...) Grab what we can, prohibit backtracking - (?|...) Branch reset - (?<name>...) Named capture - (?'name'...) Named capture - (?P<name>...) Named capture (python syntax) - (?{ code }) Embedded code, return value becomes $^R - (??{ code }) Dynamic regex, return value used as regex - (?N) Recurse into subpattern number N - (?-N), (?+N) Recurse into Nth previous/next subpattern - (?R), (?0) Recurse at the beginning of the whole pattern - (?&name) Recurse into a named subpattern - (?P>name) Recurse into a named subpattern (python syntax) - (?(cond)yes|no) - (?(cond)yes) Conditional expression, where "cond" can be: - (N) subpattern N has matched something - (<name>) named subpattern has matched something - ('name') named subpattern has matched something - (?{code}) code condition - (R) true if recursing - (RN) true if recursing into Nth subpattern - (R&name) true if recursing into named subpattern - (DEFINE) always false, no no-pattern allowed - -=head2 VARIABLES - - $_ Default variable for operators to use - - $` Everything prior to matched string - $& Entire matched string - $' Everything after to matched string - - ${^PREMATCH} Everything prior to matched string - ${^MATCH} Entire matched string - ${^POSTMATCH} Everything after to matched string - -The use of C<$`>, C<$&> or C<$'> will slow down B<all> regex use -within your program. Consult L<perlvar> for C<@-> -to see equivalent expressions that won't cause slow down. -See also L<Devel::SawAmpersand>. Starting with Perl 5.10, you -can also use the equivalent variables C<${^PREMATCH}>, C<${^MATCH}> -and C<${^POSTMATCH}>, but for them to be defined, you have to -specify the C</p> (preserve) modifier on your regular expression. - - $1, $2 ... hold the Xth captured expr - $+ Last parenthesized pattern match - $^N Holds the most recently closed capture - $^R Holds the result of the last (?{...}) expr - @- Offsets of starts of groups. $-[0] holds start of whole match - @+ Offsets of ends of groups. $+[0] holds end of whole match - %+ Named capture buffers - %- Named capture buffers, as array refs - -Captured groups are numbered according to their I<opening> paren. - -=head2 FUNCTIONS - - lc Lowercase a string - lcfirst Lowercase first char of a string - uc Uppercase a string - ucfirst Titlecase first char of a string - - pos Return or set current match position - quotemeta Quote metacharacters - reset Reset ?pattern? status - study Analyze string for optimizing matching - - split Use a regex to split a string into parts - -The first four of these are like the escape sequences C<\L>, C<\l>, -C<\U>, and C<\u>. For Titlecase, see L</Titlecase>. - -=head2 TERMINOLOGY - -=head3 Titlecase - -Unicode concept which most often is equal to uppercase, but for -certain characters like the German "sharp s" there is a difference. - -=head1 AUTHOR - -Iain Truskett. Updated by the Perl 5 Porters. - -This document may be distributed under the same terms as Perl itself. - -=head1 SEE ALSO - -=over 4 - -=item * - -L<perlretut> for a tutorial on regular expressions. - -=item * - -L<perlrequick> for a rapid tutorial. - -=item * - -L<perlre> for more details. - -=item * - -L<perlvar> for details on the variables. - -=item * - -L<perlop> for details on the operators. - -=item * - -L<perlfunc> for details on the functions. - -=item * - -L<perlfaq6> for FAQs on regular expressions. - -=item * - -L<perlrebackslash> for a reference on backslash sequences. - -=item * - -L<perlrecharclass> for a reference on character classes. - -=item * - -The L<re> module to alter behaviour and aid -debugging. - -=item * - -L<perldebug/"Debugging regular expressions"> - -=item * - -L<perluniintro>, L<perlunicode>, L<charnames> and L<perllocale> -for details on regexes and internationalisation. - -=item * - -I<Mastering Regular Expressions> by Jeffrey Friedl -(F<http://regex.info/>) for a thorough grounding and -reference on the topic. - -=back - -=head1 THANKS - -David P.C. Wollmann, -Richard Soderberg, -Sean M. Burke, -Tom Christiansen, -Jim Cromie, -and -Jeffrey Goff -for useful advice. - -=cut |