Lines Matching full:regular
89 * Extended regexps:: @command{egrep}-style regular expressions
91 * Perl regexps:: Perl-style regular expressions
104 * Regular Expressions:: Overview of regular expression syntax
132 Perl regexps:: Perl-style regular expressions
325 @cindex Extended regular expressions, choosing
326 @cindex @acronym{GNU} extensions, extended regular expressions
327 Use extended regular expressions rather than basic
328 regular expressions. Extended regexps are those that
332 @xref{Extended regexps, , Extended regular expressions}.
339 @cindex Perl-style regular expressions, choosing
340 @cindex @value{SSEDEXT}, Perl-style regular expressions
341 Use Perl-style regular expressions rather than basic
342 regular expressions. Perl-style regexps are extremely
345 Perl-style regular expressions}.
407 * Regular Expressions:: Overview of regular expression syntax
488 @cindex Address, as a regular expression
489 @cindex Line, selecting by regular expression match
490 This will select any line which matches the regular expression @var{regexp}.
494 @cindex empty regular expression
495 @cindex @value{SSEDEXT}, modifiers and the empty regular expression
496 The empty regular expression @samp{//} repeats the last regular
497 expression match (the same holds if the empty regular expression is
498 passed to the @code{s} command). Note that modifiers to regular expressions
499 are evaluated when the regular expression is compiled, thus it is invalid to
500 specify them together with the empty regular expression.
505 @cindex Slash character, in regular expressions
506 This also matches the regular expression @var{regexp},
517 @cindex Perl-style regular expressions, case-insensitive
519 The @code{I} modifier to regular-expression matching is a @acronym{GNU}
528 @cindex Perl-style regular expressions, multiline
529 The @code{M} modifier to regular-expression matching is a @value{SSED}
536 in basic or extended regular expression modes)
548 @cindex Perl-style regular expressions, single line
549 The @code{S} modifier to regular-expression matching is only valid
558 @cindex Perl-style regular expressions, extended
559 The @code{X} modifier to regular-expression matching is also
612 regular expression.
637 @node Regular Expressions
638 @section Overview of Regular Expression Syntax
640 To know how to use @command{sed}, people should understand regular
641 expressions (@dfn{regexp} for short). A regular expression
654 itself. The power of regular expressions comes from the
659 of regular expression syntax as used in @command{sed}.
666 @cindex @acronym{GNU} extensions, to basic regular expressions
668 preceding regular expression, which must be an ordinary character, a
671 postfixed regular expression can also be followed by @code{*}; for
674 the start of a regular expression or subexpression, but many
679 @cindex @acronym{GNU} extensions, to basic regular expressions
683 @cindex @acronym{GNU} extensions, to basic regular expressions
702 @cindex @acronym{GNU} extensions, to basic regular expressions
733 regular expression or subexpression (that is, after @code{\(} or
741 of the regular expression or subexpression (that is, before @code{\)}
774 @cindex @acronym{GNU} extensions, to basic regular expressions
776 parentheses to use complex alternative regular expressions.
784 @code{$}, but less tightly than the other regular expression
789 subexpression in the regular expression. This is called a @dfn{back
807 @cindex Greedy regular expression matching
808 Note that the regular expression matcher is greedy, i.e., matches
972 @cindex Backreferences, in regular expressions
1082 @cindex Perl-style regular expressions, case-insensitive
1084 The @code{I} modifier to regular-expression matching is a @acronym{GNU}
1092 @cindex Perl-style regular expressions, multiline
1094 The @code{M} modifier to regular-expression matching is a @value{SSED}
1101 in basic or extended regular expression modes)
1113 @cindex Perl-style regular expressions, single line
1114 The @code{S} modifier to regular-expression matching is only valid
1123 @cindex Perl-style regular expressions, extended
1124 The @code{X} modifier to regular-expression matching is also
1508 @section @acronym{GNU} Extensions for Escapes in Regular Expressions
1520 extensions, with the exception of @code{\n}. In basic regular
1571 with the @code{o} is active in the normal or extended @sc{posix} regular
1583 regular expressions:
1659 the regular expressions to be matched---this is a common
2691 There are some size limitations in the regular expression
2699 regular expressions.}, assertions, and other types of
2709 regular expressions and those that @option{-R} recognizes.
2855 @cindex @acronym{GNU} extensions, to basic regular expressions
2857 @command{sed} uses the @sc{posix} basic regular expression syntax. According to
2863 As in all @acronym{GNU} programs that use @sc{posix} basic regular
2943 @acronym{GNU} libc's regular expression matcher instead of compiling the
2945 the regular expression @code{^[a-z]$} matches the string @samp{aa},
2973 @appendix Extended regular expressions
2974 @cindex Extended regular expressions, syntax
2976 The only difference between basic and extended regular expressions is in
2978 and braces (@samp{@{@}}). While basic regular expressions require
2980 when using extended regular expressions you must escape them if
2987 becomes @samp{abc\?} when using extended regular expressions. It matches
2991 becomes @samp{c+} when using extended regular expressions. It matches
2995 becomes @samp{a@{3,@}} when using extended regular expressions. It matches
2999 becomes @samp{(abc)@{2,3@}} when using extended regular expressions. It
3003 becomes @samp{(abc*)\1} when using extended regular expressions.
3004 Backreferences must still be escaped when using extended regular
3010 @appendix Perl-style regular expressions
3011 @cindex Perl-style regular expressions, syntax
3014 with the free @sc{pcre} regular expression matcher; it was written by Philip Hazel.}
3016 Perl introduced several extensions to regular expressions, some
3017 of them incompatible with the syntax of regular expressions
3037 You can toggle modifiers in the middle of a regular expression
3043 @cindex Greedy regular expression matching
3095 @cindex Perl-style regular expressions, escaped sequences
3111 @cindex Perl-style regular expressions, backreferences
3158 @cindex Perl-style regular expressions, character classes
3179 @cindex Perl-style regular expressions, assertions
3223 @cindex Perl-style regular expressions, newlines
3249 @cindex Perl-style regular expressions, multiline
3261 @cindex Perl-style regular expressions, multiline
3267 @cindex Perl-style regular expressions, single line
3279 @cindex Perl-style regular expressions, character classes
3304 @cindex Perl-style regular expressions, case-insensitive
3311 @cindex Perl-style regular expressions, single line
3312 @cindex Perl-style regular expressions, multiline
3427 @cindex Perl-style regular expressions, toggling options
3428 @cindex Perl-style regular expressions, case-insensitive
3429 @cindex Perl-style regular expressions, multiline
3430 @cindex Perl-style regular expressions, single line
3431 @cindex Perl-style regular expressions, extended
3506 @cindex Perl-style regular expressions, non-capturing subpatterns
3563 @cindex Perl-style regular expressions, repetitions
3654 @cindex Greedy regular expression matching
3655 @cindex Perl-style regular expressions, stingy repetitions
3713 @cindex Perl-style regular expressions, single line
3745 @cindex Perl-style regular expressions, backreferences
3828 @cindex Perl-style regular expressions, assertions
3829 @cindex Perl-style regular expressions, asserting subpatterns
3839 @cindex Perl-style regular expressions, lookahead subpatterns
3868 @cindex Perl-style regular expressions, lookbehind subpatterns
3894 is permitted, but the apparently equivalent regular expression
3983 @cindex Perl-style regular expressions, non-backtracking subpatterns
4031 @cindex Perl-style regular expressions, lookbehind subpatterns
4075 common: they happen for example in a regular expression
4117 @cindex Perl-style regular expressions, conditional subpatterns
4159 @cindex Perl-style regular expressions, lookahead subpatterns
4182 @cindex Perl-style regular expressions, recursive patterns
4183 @cindex Perl-style regular expressions, recursion
4190 provided an experimental facility that allows regular
4249 @cindex Perl-style regular expressions, comments
4256 @cindex Perl-style regular expressions, extended
