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<a name="Regexp-Summary"></a>
<div class="header">
<p>
Next: <a href="Regexp-Details.html#Regexp-Details" accesskey="n" rel="next">Regexp Details</a>, Up: <a href="Regexps.html#Regexps" accesskey="u" rel="up">Regexps</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="General-Index.html#General-Index" title="Index" rel="index">Index</a>]</p>
</div>
<hr>
<a name="Regexp-Syntax-Summary"></a>
<h4 class="subsection">7.4.1 Regexp Syntax Summary</h4>

<p>This is a quick-reference summary of the regular expression syntax
used in Monotone.
</p>
<a name="Quoting"></a>
<h4 class="subsubheading">Quoting</h4>

<dl compact="compact">
<dt><code>\<var>x</var></code></dt>
<dd><p>where <var>x</var> is non-alphanumeric is a literal <var>x</var>
</p></dd>
<dt><code>\Q...\E</code></dt>
<dd><p>treat enclosed characters as literal
</p></dd>
</dl>

<a name="Characters"></a>
<h4 class="subsubheading">Characters</h4>

<dl compact="compact">
<dt><code>\a</code></dt>
<dd><p>alarm, that is, the BEL character (hex 07)
</p></dd>
<dt><code>\c<var>x</var></code></dt>
<dd><p>&ldquo;control-<var>x</var>&rdquo;, where <var>x</var> is any character
</p></dd>
<dt><code>\e</code></dt>
<dd><p>escape (hex 1B)
</p></dd>
<dt><code>\f</code></dt>
<dd><p>formfeed (hex 0C)
</p></dd>
<dt><code>\n</code></dt>
<dd><p>newline (hex 0A)
</p></dd>
<dt><code>\r</code></dt>
<dd><p>carriage return (hex 0D)
</p></dd>
<dt><code>\t</code></dt>
<dd><p>tab (hex 09)
</p></dd>
<dt><code>\<var>ddd</var></code></dt>
<dd><p>character with octal code <var>ddd</var>, or backreference
</p></dd>
<dt><code>\x<var>hh</var></code></dt>
<dd><p>character with hex code <var>hh</var>
</p></dd>
<dt><code>\x{<var>hhh...</var>}</code></dt>
<dd><p>character with hex code <var>hhh...</var>
</p></dd>
</dl>

<a name="Character-Types"></a>
<h4 class="subsubheading">Character Types</h4>

<dl compact="compact">
<dt><code>.</code></dt>
<dd><p>any character except newline;
               in dotall mode, any character whatsoever
</p></dd>
<dt><code>\C</code></dt>
<dd><p>one byte, even in UTF-8 mode (best avoided)
</p></dd>
<dt><code>\d</code></dt>
<dd><p>a decimal digit
</p></dd>
<dt><code>\D</code></dt>
<dd><p>a character that is not a decimal digit
</p></dd>
<dt><code>\h</code></dt>
<dd><p>a horizontal whitespace character
</p></dd>
<dt><code>\H</code></dt>
<dd><p>a character that is not a horizontal whitespace character
</p></dd>
<dt><code>\p{<var>xx</var>}</code></dt>
<dd><p>a character with the <var>xx</var> property
</p></dd>
<dt><code>\P{<var>xx</var>}</code></dt>
<dd><p>a character without the <var>xx</var> property
</p></dd>
<dt><code>\R</code></dt>
<dd><p>a newline sequence
</p></dd>
<dt><code>\s</code></dt>
<dd><p>a whitespace character
</p></dd>
<dt><code>\S</code></dt>
<dd><p>a character that is not a whitespace character
</p></dd>
<dt><code>\v</code></dt>
<dd><p>a vertical whitespace character
</p></dd>
<dt><code>\V</code></dt>
<dd><p>a character that is not a vertical whitespace character
</p></dd>
<dt><code>\w</code></dt>
<dd><p>a &ldquo;word&rdquo; character
</p></dd>
<dt><code>\W</code></dt>
<dd><p>a &ldquo;non-word&rdquo; character
</p></dd>
<dt><code>\X</code></dt>
<dd><p>an extended Unicode sequence
</p></dd>
</dl>

<p>&lsquo;<samp>\d</samp>&rsquo;, &lsquo;<samp>\D</samp>&rsquo;, &lsquo;<samp>\s</samp>&rsquo;, &lsquo;<samp>\S</samp>&rsquo;, &lsquo;<samp>\w</samp>&rsquo;, and &lsquo;<samp>\W</samp>&rsquo;
recognize only ASCII characters.
</p>
<a name="General-category-property-codes-for-_005cp-and-_005cP"></a>
<h4 class="subsubheading">General category property codes for &lsquo;<samp>\p</samp>&rsquo; and &lsquo;<samp>\P</samp>&rsquo;</h4>

<dl compact="compact">
<dt><code>C</code></dt>
<dd><p>Other
</p></dd>
<dt><code>Cc</code></dt>
<dd><p>Control
</p></dd>
<dt><code>Cf</code></dt>
<dd><p>Format
</p></dd>
<dt><code>Cn</code></dt>
<dd><p>Unassigned
</p></dd>
<dt><code>Co</code></dt>
<dd><p>Private use
</p></dd>
<dt><code>Cs</code></dt>
<dd><p>Surrogate
</p>
</dd>
<dt><code>L</code></dt>
<dd><p>Letter
</p></dd>
<dt><code>Ll</code></dt>
<dd><p>Lower case letter
</p></dd>
<dt><code>Lm</code></dt>
<dd><p>Modifier letter
</p></dd>
<dt><code>Lo</code></dt>
<dd><p>Other letter
</p></dd>
<dt><code>Lt</code></dt>
<dd><p>Title case letter
</p></dd>
<dt><code>Lu</code></dt>
<dd><p>Upper case letter
</p></dd>
<dt><code>L&amp;</code></dt>
<dd><p>Ll, Lu, or Lt
</p>
</dd>
<dt><code>M</code></dt>
<dd><p>Mark
</p></dd>
<dt><code>Mc</code></dt>
<dd><p>Spacing mark
</p></dd>
<dt><code>Me</code></dt>
<dd><p>Enclosing mark
</p></dd>
<dt><code>Mn</code></dt>
<dd><p>Non-spacing mark
</p>
</dd>
<dt><code>N</code></dt>
<dd><p>Number
</p></dd>
<dt><code>Nd</code></dt>
<dd><p>Decimal number
</p></dd>
<dt><code>Nl</code></dt>
<dd><p>Letter number
</p></dd>
<dt><code>No</code></dt>
<dd><p>Other number
</p>
</dd>
<dt><code>P</code></dt>
<dd><p>Punctuation
</p></dd>
<dt><code>Pc</code></dt>
<dd><p>Connector punctuation
</p></dd>
<dt><code>Pd</code></dt>
<dd><p>Dash punctuation
</p></dd>
<dt><code>Pe</code></dt>
<dd><p>Close punctuation
</p></dd>
<dt><code>Pf</code></dt>
<dd><p>Final punctuation
</p></dd>
<dt><code>Pi</code></dt>
<dd><p>Initial punctuation
</p></dd>
<dt><code>Po</code></dt>
<dd><p>Other punctuation
</p></dd>
<dt><code>Ps</code></dt>
<dd><p>Open punctuation
</p>
</dd>
<dt><code>S</code></dt>
<dd><p>Symbol
</p></dd>
<dt><code>Sc</code></dt>
<dd><p>Currency symbol
</p></dd>
<dt><code>Sk</code></dt>
<dd><p>Modifier symbol
</p></dd>
<dt><code>Sm</code></dt>
<dd><p>Mathematical symbol
</p></dd>
<dt><code>So</code></dt>
<dd><p>Other symbol
</p>
</dd>
<dt><code>Z</code></dt>
<dd><p>Separator
</p></dd>
<dt><code>Zl</code></dt>
<dd><p>Line separator
</p></dd>
<dt><code>Zp</code></dt>
<dd><p>Paragraph separator
</p></dd>
<dt><code>Zs</code></dt>
<dd><p>Space separator
</p></dd>
</dl>

<a name="Script-names-for-_005cp-and-_005cP"></a>
<h4 class="subsubheading">Script names for &lsquo;<samp>\p</samp>&rsquo; and &lsquo;<samp>\P</samp>&rsquo;</h4>

<p>Arabic,
Armenian,
Balinese,
Bengali,
Bopomofo,
Braille,
Buginese,
Buhid,
Canadian_Aboriginal,
Cherokee,
Common,
Coptic,
Cuneiform,
Cypriot,
Cyrillic,
Deseret,
Devanagari,
Ethiopic,
Georgian,
Glagolitic,
Gothic,
Greek,
Gujarati,
Gurmukhi,
Han,
Hangul,
Hanunoo,
Hebrew,
Hiragana,
Inherited,
Kannada,
Katakana,
Kharoshthi,
Khmer,
Lao,
Latin,
Limbu,
Linear_B,
Malayalam,
Mongolian,
Myanmar,
New_Tai_Lue,
Nko,
Ogham,
Old_Italic,
Old_Persian,
Oriya,
Osmanya,
Phags_Pa,
Phoenician,
Runic,
Shavian,
Sinhala,
Syloti_Nagri,
Syriac,
Tagalog,
Tagbanwa,
Tai_Le,
Tamil,
Telugu,
Thaana,
Thai,
Tibetan,
Tifinagh,
Ugaritic,
Yi.
</p>
<a name="Character-Classes"></a>
<h4 class="subsubheading">Character Classes</h4>

<dl compact="compact">
<dt><code>[...]</code></dt>
<dd><p>positive character class
</p></dd>
<dt><code>[^...]</code></dt>
<dd><p>negative character class
</p></dd>
<dt><code>[<var>x</var>-<var>y</var>]</code></dt>
<dd><p>range (can be used for hex characters)
</p></dd>
<dt><code>[[:<var>xxx</var>:]]</code></dt>
<dd><p>positive POSIX named set
</p></dd>
<dt><code>[[:^<var>xxx</var>:]]</code></dt>
<dd><p>negative POSIX named set
</p>
</dd>
<dt><code>alnum</code></dt>
<dd><p>alphanumeric
</p></dd>
<dt><code>alpha</code></dt>
<dd><p>alphabetic
</p></dd>
<dt><code>ascii</code></dt>
<dd><p>0-127
</p></dd>
<dt><code>blank</code></dt>
<dd><p>space or tab
</p></dd>
<dt><code>cntrl</code></dt>
<dd><p>control character
</p></dd>
<dt><code>digit</code></dt>
<dd><p>decimal digit
</p></dd>
<dt><code>graph</code></dt>
<dd><p>printing, excluding space
</p></dd>
<dt><code>lower</code></dt>
<dd><p>lower case letter
</p></dd>
<dt><code>print</code></dt>
<dd><p>printing, including space
</p></dd>
<dt><code>punct</code></dt>
<dd><p>printing, excluding alphanumeric
</p></dd>
<dt><code>space</code></dt>
<dd><p>whitespace
</p></dd>
<dt><code>upper</code></dt>
<dd><p>upper case letter
</p></dd>
<dt><code>word</code></dt>
<dd><p>same as &lsquo;<samp>\w</samp>&rsquo;
</p></dd>
<dt><code>xdigit</code></dt>
<dd><p>hexadecimal digit
</p></dd>
</dl>

<p>In PCRE, POSIX character set names recognize only ASCII
characters. You can use &lsquo;<samp>\Q...\E</samp>&rsquo; inside a character class.
</p>
<a name="Quantifiers"></a>
<h4 class="subsubheading">Quantifiers</h4>

<dl compact="compact">
<dt><code>?</code></dt>
<dd><p>0 or 1, greedy
</p></dd>
<dt><code>?+</code></dt>
<dd><p>0 or 1, possessive
</p></dd>
<dt><code>??</code></dt>
<dd><p>0 or 1, lazy
</p></dd>
<dt><code>*</code></dt>
<dd><p>0 or more, greedy
</p></dd>
<dt><code>*+</code></dt>
<dd><p>0 or more, possessive
</p></dd>
<dt><code>*?</code></dt>
<dd><p>0 or more, lazy
</p></dd>
<dt><code>+</code></dt>
<dd><p>1 or more, greedy
</p></dd>
<dt><code>++</code></dt>
<dd><p>1 or more, possessive
</p></dd>
<dt><code>+?</code></dt>
<dd><p>1 or more, lazy
</p></dd>
<dt><code>{<var>n</var>}</code></dt>
<dd><p>exactly <var>n</var>
</p></dd>
<dt><code>{<var>n</var>,<var>m</var>}</code></dt>
<dd><p>at least <var>n</var>, no more than <var>m</var>, greedy
</p></dd>
<dt><code>{<var>n</var>,<var>m</var>}+</code></dt>
<dd><p>at least <var>n</var>, no more than <var>m</var>, possessive
</p></dd>
<dt><code>{<var>n</var>,<var>m</var>}?</code></dt>
<dd><p>at least <var>n</var>, no more than <var>m</var>, lazy
</p></dd>
<dt><code>{<var>n</var>,}</code></dt>
<dd><p><var>n</var> or more, greedy
</p></dd>
<dt><code>{<var>n</var>,}+</code></dt>
<dd><p><var>n</var> or more, possessive
</p></dd>
<dt><code>{<var>n</var>,}?</code></dt>
<dd><p><var>n</var> or more, lazy
</p></dd>
</dl>

<a name="Anchors-and-Simple-Assertions"></a>
<h4 class="subsubheading">Anchors and Simple Assertions</h4>

<dl compact="compact">
<dt><code>\b</code></dt>
<dd><p>word boundary
</p></dd>
<dt><code>\B</code></dt>
<dd><p>not a word boundary
</p></dd>
<dt><code>^</code></dt>
<dd><p>start of subject
               also after internal newline in multiline mode
</p></dd>
<dt><code>\A</code></dt>
<dd><p>start of subject
</p></dd>
<dt><code>$</code></dt>
<dd><p>end of subject
               also before newline at end of subject
               also before internal newline in multiline mode
</p></dd>
<dt><code>\Z</code></dt>
<dd><p>end of subject
               also before newline at end of subject
</p></dd>
<dt><code>\z</code></dt>
<dd><p>end of subject
</p></dd>
<dt><code>\G</code></dt>
<dd><p>first matching position in subject
</p></dd>
</dl>

<a name="Match-Point-Reset"></a>
<h4 class="subsubheading">Match Point Reset</h4>

<dl compact="compact">
<dt><code>\K</code></dt>
<dd><p>reset start of match
</p></dd>
</dl>

<a name="Alternation"></a>
<h4 class="subsubheading">Alternation</h4>

<dl compact="compact">
<dt><code><var>expr</var>|<var>expr</var>|<var>expr</var>...</code></dt>
</dl>

<a name="Capturing"></a>
<h4 class="subsubheading">Capturing</h4>

<dl compact="compact">
<dt><code>(...)</code></dt>
<dd><p>capturing group
</p></dd>
<dt><code>(?&lt;<var>name</var>&gt;...)</code></dt>
<dd><p>named capturing group (like Perl)
</p></dd>
<dt><code>(?'<var>name</var>'...)</code></dt>
<dd><p>named capturing group (like Perl)
</p></dd>
<dt><code>(?P&lt;<var>name</var>&gt;...)</code></dt>
<dd><p>named capturing group (like Python)
</p></dd>
<dt><code>(?:...)</code></dt>
<dd><p>non-capturing group
</p></dd>
<dt><code>(?|...)</code></dt>
<dd><p>non-capturing group; reset group numbers for
  capturing groups in each alternative
</p></dd>
</dl>

<a name="Atomic-Groups"></a>
<h4 class="subsubheading">Atomic Groups</h4>

<dl compact="compact">
<dt><code>(?&gt;...)</code></dt>
<dd><p>atomic, non-capturing group
</p></dd>
</dl>

<a name="Comment"></a>
<h4 class="subsubheading">Comment</h4>

<dl compact="compact">
<dt><code>(?#....)</code></dt>
<dd><p>comment (not nestable)
</p></dd>
</dl>

<a name="Option-Setting"></a>
<h4 class="subsubheading">Option Setting</h4>

<dl compact="compact">
<dt><code>(?i)</code></dt>
<dd><p>caseless
</p></dd>
<dt><code>(?J)</code></dt>
<dd><p>allow duplicate names
</p></dd>
<dt><code>(?m)</code></dt>
<dd><p>multiline
</p></dd>
<dt><code>(?s)</code></dt>
<dd><p>single line (dotall)
</p></dd>
<dt><code>(?U)</code></dt>
<dd><p>default ungreedy (lazy)
</p></dd>
<dt><code>(?x)</code></dt>
<dd><p>extended (ignore white space)
</p></dd>
<dt><code>(?-...)</code></dt>
<dd><p>unset option(s)
</p></dd>
</dl>

<a name="Lookahead-and-Lookbehind-Assertions"></a>
<h4 class="subsubheading">Lookahead and Lookbehind Assertions</h4>

<dl compact="compact">
<dt><code>(?=...)</code></dt>
<dd><p>positive look ahead
</p></dd>
<dt><code>(?!...)</code></dt>
<dd><p>negative look ahead
</p></dd>
<dt><code>(?&lt;=...)</code></dt>
<dd><p>positive look behind
</p></dd>
<dt><code>(?&lt;!...)</code></dt>
<dd><p>negative look behind
</p></dd>
</dl>

<p>Each top-level branch of a look behind must be of a fixed length.
</p>
<a name="Backreferences"></a>
<h4 class="subsubheading">Backreferences</h4>

<dl compact="compact">
<dt><code>\<var>n</var></code></dt>
<dd><p>reference by number (can be ambiguous)
</p></dd>
<dt><code>\g<var>n</var></code></dt>
<dd><p>reference by number
</p></dd>
<dt><code>\g{<var>n</var>}</code></dt>
<dd><p>reference by number
</p></dd>
<dt><code>\g{-<var>n</var>}</code></dt>
<dd><p>relative reference by number
</p></dd>
<dt><code>\k&lt;<var>name</var>&gt;</code></dt>
<dd><p>reference by name (like Perl)
</p></dd>
<dt><code>\k'<var>name</var>'</code></dt>
<dd><p>reference by name (like Perl)
</p></dd>
<dt><code>\g{<var>name</var>}</code></dt>
<dd><p>reference by name (like Perl)
</p></dd>
<dt><code>\k{<var>name</var>}</code></dt>
<dd><p>reference by name (like .NET)
</p></dd>
<dt><code>(?P=<var>name</var>)</code></dt>
<dd><p>reference by name (like Python)
</p></dd>
</dl>

<a name="Subroutine-References-_0028possibly-recursive_0029"></a>
<h4 class="subsubheading">Subroutine References (possibly recursive)</h4>

<dl compact="compact">
<dt><code>(?R)</code></dt>
<dd><p>recurse whole pattern
</p></dd>
<dt><code>(?<var>n</var>)</code></dt>
<dd><p>call subpattern by absolute number
</p></dd>
<dt><code>(?+<var>n</var>)</code></dt>
<dd><p>call subpattern by relative number
</p></dd>
<dt><code>(?-<var>n</var>)</code></dt>
<dd><p>call subpattern by relative number
</p></dd>
<dt><code>(?&amp;<var>name</var>)</code></dt>
<dd><p>call subpattern by name (like Perl)
</p></dd>
<dt><code>(?P&gt;<var>name</var>)</code></dt>
<dd><p>call subpattern by name (like Python)
</p></dd>
</dl>

<a name="Conditional-Patterns"></a>
<h4 class="subsubheading">Conditional Patterns</h4>

<dl compact="compact">
<dt><code>(?(<var>condition</var>)<var>yes-pattern</var>)</code></dt>
<dt><code>(?(<var>condition</var>)<var>yes-pattern</var>|<var>no-pattern</var>)</code></dt>
<dt><code>(?(<var>n</var>)...</code></dt>
<dd><p>absolute reference condition
</p></dd>
<dt><code>(?(+<var>n</var>)...</code></dt>
<dd><p>relative reference condition
</p></dd>
<dt><code>(?(-<var>n</var>)...</code></dt>
<dd><p>relative reference condition
</p></dd>
<dt><code>(?(&lt;<var>name</var>&gt;)...</code></dt>
<dd><p>named reference condition (like Perl)
</p></dd>
<dt><code>(?('<var>name</var>')...</code></dt>
<dd><p>named reference condition (like Perl)
</p></dd>
<dt><code>(?(<var>name</var>)...</code></dt>
<dd><p>named reference condition (PCRE only)
</p></dd>
<dt><code>(?(R)...</code></dt>
<dd><p>overall recursion condition
</p></dd>
<dt><code>(?(R<var>n</var>)...</code></dt>
<dd><p>specific group recursion condition
</p></dd>
<dt><code>(?(R&amp;<var>name</var>)...</code></dt>
<dd><p>specific recursion condition
</p></dd>
<dt><code>(?(DEFINE)...</code></dt>
<dd><p>define subpattern for reference
</p></dd>
<dt><code>(?(assert)...</code></dt>
<dd><p>assertion condition
</p></dd>
</dl>

<a name="Backtracking-Control"></a>
<h4 class="subsubheading">Backtracking Control</h4>

<p>The following act immediately they are reached:
</p>
<dl compact="compact">
<dt><code>(*ACCEPT)</code></dt>
<dd><p>force successful match
</p></dd>
<dt><code>(*FAIL)</code></dt>
<dd><p>force backtrack; synonym &lsquo;<samp>(*F)</samp>&rsquo;
</p></dd>
</dl>

<p>The following act only when a subsequent match failure causes a backtrack to
reach them. They all force a match failure, but they differ in what happens
afterwards. Those that advance the start-of-match point do so only if the
pattern is not anchored.
</p>
<dl compact="compact">
<dt><code>(*COMMIT)</code></dt>
<dd><p>overall failure, no advance of starting point
</p></dd>
<dt><code>(*PRUNE)</code></dt>
<dd><p>advance to next starting character
</p></dd>
<dt><code>(*SKIP)</code></dt>
<dd><p>advance start to current matching position
</p></dd>
<dt><code>(*THEN)</code></dt>
<dd><p>local failure, backtrack to next alternation
</p></dd>
</dl>

<a name="Newline-Conventions"></a>
<h4 class="subsubheading">Newline Conventions</h4>

<p>These are recognized only at the very start of the pattern or after a
&lsquo;<samp>(*BSR_...)</samp>&rsquo; option.
</p>
<dl compact="compact">
<dt><code>(*CR)</code></dt>
<dt><code>(*LF)</code></dt>
<dt><code>(*CRLF)</code></dt>
<dt><code>(*ANYCRLF)</code></dt>
<dt><code>(*ANY)</code></dt>
</dl>

<a name="What-_005cR-Matches"></a>
<h4 class="subsubheading">What &lsquo;<samp>\R</samp>&rsquo; Matches</h4>

<p>These are recognized only at the very start of the pattern or after a
&lsquo;<samp>(*...)</samp>&rsquo; option that sets the newline convention.
</p>
<dl compact="compact">
<dt><code>(*BSR_ANYCRLF)</code></dt>
<dt><code>(*BSR_UNICODE)</code></dt>
</dl>

<hr>
<div class="header">
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