Highlight the differences between \Z in Boost and Perl.

Regenerate docs.
Fixes #3899.

[SVN r59512]

doc/html/boost_regex/syntax/perl_syntax.html

@@ -28,7 +28,7 @@
       Syntax</a>
 </h3></div></div></div>
 <a name="boost_regex.syntax.perl_syntax.synopsis"></a><h4>
-<a name="id787810"></a>
+<a name="id751450"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.synopsis">Synopsis</a>
       </h4>
 <p>
@@ -43,7 +43,7 @@
 </span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span> <span class="identifier">e2</span><span class="special">(</span><span class="identifier">my_expression</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span><span class="special">::</span><span class="identifier">perl</span><span class="special">|</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">regex</span><span class="special">::</span><span class="identifier">icase</span><span class="special">);</span>
 </pre>
 <a name="boost_regex.syntax.perl_syntax.perl_regular_expression_syntax"></a><h4>
-<a name="id787958"></a>
+<a name="id751598"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.perl_regular_expression_syntax">Perl
         Regular Expression Syntax</a>
       </h4>
@@ -53,7 +53,7 @@
       </p>
 <pre class="programlisting">.[{()\*+?|^$</pre>
 <a name="boost_regex.syntax.perl_syntax.wildcard"></a><h5>
-<a name="id787982"></a>
+<a name="id751622"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.wildcard">Wildcard</a>
       </h5>
 <p>
@@ -73,7 +73,7 @@
         </li>
 </ul></div>
 <a name="boost_regex.syntax.perl_syntax.anchors"></a><h5>
-<a name="id788029"></a>
+<a name="id751669"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.anchors">Anchors</a>
       </h5>
 <p>
@@ -83,7 +83,7 @@
         A '$' character shall match the end of a line.
       </p>
 <a name="boost_regex.syntax.perl_syntax.marked_sub_expressions"></a><h5>
-<a name="id788050"></a>
+<a name="id751690"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.marked_sub_expressions">Marked
         sub-expressions</a>
       </h5>
@@ -94,7 +94,7 @@
         can also repeated, or referred to by a back-reference.
       </p>
 <a name="boost_regex.syntax.perl_syntax.non_marking_grouping"></a><h5>
-<a name="id788077"></a>
+<a name="id751717"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.non_marking_grouping">Non-marking
         grouping</a>
       </h5>
@@ -107,7 +107,7 @@
         without splitting out any separate sub-expressions.
       </p>
 <a name="boost_regex.syntax.perl_syntax.repeats"></a><h5>
-<a name="id788113"></a>
+<a name="id751753"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.repeats">Repeats</a>
       </h5>
 <p>
@@ -188,7 +188,7 @@
         to be applied to.
       </p>
 <a name="boost_regex.syntax.perl_syntax.non_greedy_repeats"></a><h5>
-<a name="id788349"></a>
+<a name="id751989"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.non_greedy_repeats">Non greedy
         repeats</a>
       </h5>
@@ -218,7 +218,7 @@
         while consuming as little input as possible.
       </p>
 <a name="boost_regex.syntax.perl_syntax.pocessive_repeats"></a><h5>
-<a name="id788408"></a>
+<a name="id752048"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.pocessive_repeats">Pocessive
         repeats</a>
       </h5>
@@ -250,7 +250,7 @@
         while giving nothing back.
       </p>
 <a name="boost_regex.syntax.perl_syntax.back_references"></a><h5>
-<a name="id788467"></a>
+<a name="id752107"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.back_references">Back references</a>
       </h5>
 <p>
@@ -360,7 +360,7 @@
         named "two".
       </p>
 <a name="boost_regex.syntax.perl_syntax.alternation"></a><h5>
-<a name="id788686"></a>
+<a name="id752326"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.alternation">Alternation</a>
       </h5>
 <p>
@@ -387,7 +387,7 @@
         <code class="literal">(?:abc)??</code> has exactly the same effect.
       </p>
 <a name="boost_regex.syntax.perl_syntax.character_sets"></a><h5>
-<a name="id788755"></a>
+<a name="id752395"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.character_sets">Character sets</a>
       </h5>
 <p>
@@ -399,7 +399,7 @@
         A bracket expression may contain any combination of the following:
       </p>
 <a name="boost_regex.syntax.perl_syntax.single_characters"></a><h6>
-<a name="id788786"></a>
+<a name="id753809"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.single_characters">Single characters</a>
       </h6>
 <p>
@@ -407,7 +407,7 @@
         'b', or 'c'.
       </p>
 <a name="boost_regex.syntax.perl_syntax.character_ranges"></a><h6>
-<a name="id788807"></a>
+<a name="id753830"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.character_ranges">Character
         ranges</a>
       </h6>
@@ -421,7 +421,7 @@
         sensitive.
       </p>
 <a name="boost_regex.syntax.perl_syntax.negation"></a><h6>
-<a name="id788840"></a>
+<a name="id753863"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.negation">Negation</a>
       </h6>
 <p>
@@ -430,7 +430,7 @@
         matches any character that is not in the range <code class="literal">a-c</code>.
       </p>
 <a name="boost_regex.syntax.perl_syntax.character_classes"></a><h6>
-<a name="id788867"></a>
+<a name="id753890"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.character_classes">Character
         classes</a>
       </h6>
@@ -441,7 +441,7 @@
         class names</a>.
       </p>
 <a name="boost_regex.syntax.perl_syntax.collating_elements"></a><h6>
-<a name="id788900"></a>
+<a name="id753923"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.collating_elements">Collating
         Elements</a>
       </h6>
@@ -463,7 +463,7 @@
         matches a <code class="literal">\0</code> character.
       </p>
 <a name="boost_regex.syntax.perl_syntax.equivalence_classes"></a><h6>
-<a name="id788962"></a>
+<a name="id753985"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.equivalence_classes">Equivalence
         classes</a>
       </h6>
@@ -480,7 +480,7 @@
         or even all locales on one platform.
       </p>
 <a name="boost_regex.syntax.perl_syntax.escaped_characters"></a><h6>
-<a name="id789010"></a>
+<a name="id754033"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.escaped_characters">Escaped
         Characters</a>
       </h6>
@@ -492,7 +492,7 @@
         is <span class="emphasis"><em>not</em></span> a "word" character.
       </p>
 <a name="boost_regex.syntax.perl_syntax.combinations"></a><h6>
-<a name="id789079"></a>
+<a name="id754101"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.combinations">Combinations</a>
       </h6>
 <p>
@@ -500,7 +500,7 @@
         <code class="literal">[[:digit:]a-c[.NUL.]]</code>.
       </p>
 <a name="boost_regex.syntax.perl_syntax.escapes"></a><h5>
-<a name="id789100"></a>
+<a name="id754123"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.escapes">Escapes</a>
       </h5>
 <p>
@@ -692,7 +692,7 @@
 </tbody>
 </table></div>
 <a name="boost_regex.syntax.perl_syntax._quot_single_character_quot__character_classes_"></a><h6>
-<a name="id789784"></a>
+<a name="id754511"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax._quot_single_character_quot__character_classes_">"Single
         character" character classes:</a>
       </h6>
@@ -894,7 +894,7 @@
 </tbody>
 </table></div>
 <a name="boost_regex.syntax.perl_syntax.character_properties"></a><h6>
-<a name="id790384"></a>
+<a name="id755111"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.character_properties">Character
         Properties</a>
       </h6>
@@ -1002,7 +1002,7 @@
         as does <code class="literal">\p{digit}</code>.
       </p>
 <a name="boost_regex.syntax.perl_syntax.word_boundaries"></a><h6>
-<a name="id790673"></a>
+<a name="id755400"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.word_boundaries">Word Boundaries</a>
       </h6>
 <p>
@@ -1021,7 +1021,7 @@
         <code class="literal">\B</code> Matches only when not at a word boundary.
       </p>
 <a name="boost_regex.syntax.perl_syntax.buffer_boundaries"></a><h6>
-<a name="id790724"></a>
+<a name="id755451"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.buffer_boundaries">Buffer boundaries</a>
       </h6>
 <p>
@@ -1036,17 +1036,19 @@
         \' Matches at the end of a buffer only.
       </p>
 <p>
-        \A Matches at the start of a buffer only (the same as \`).
+        \A Matches at the start of a buffer only (the same as <code class="literal">\\\`</code>).
       </p>
 <p>
-        \z Matches at the end of a buffer only (the same as \').
+        \z Matches at the end of a buffer only (the same as <code class="literal">\\'</code>).
       </p>
 <p>
-        \Z Matches an optional sequence of newlines at the end of a buffer: equivalent
-        to the regular expression <code class="literal">\n*\z</code>
+        \Z Matches a zero-width assertion consisting of an optional sequence of newlines
+        at the end of a buffer: equivalent to the regular expression <code class="literal">(?=\v*\z)</code>.
+        Note that this is subtly different from Perl which behaves as if matching
+        <code class="literal">(?=\n?\z)</code>.
       </p>
 <a name="boost_regex.syntax.perl_syntax.continuation_escape"></a><h6>
-<a name="id790765"></a>
+<a name="id755509"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.continuation_escape">Continuation
         Escape</a>
       </h6>
@@ -1058,7 +1060,7 @@
         one ended.
       </p>
 <a name="boost_regex.syntax.perl_syntax.quoting_escape"></a><h6>
-<a name="id790787"></a>
+<a name="id755531"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.quoting_escape">Quoting escape</a>
       </h6>
 <p>
@@ -1071,7 +1073,7 @@
 <span class="special">\*+</span><span class="identifier">aaa</span>
 </pre>
 <a name="boost_regex.syntax.perl_syntax.unicode_escapes"></a><h6>
-<a name="id790834"></a>
+<a name="id755577"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.unicode_escapes">Unicode escapes</a>
       </h6>
 <p>
@@ -1081,7 +1083,7 @@
         followed by a sequence of zero or more combining characters.
       </p>
 <a name="boost_regex.syntax.perl_syntax.matching_line_endings"></a><h6>
-<a name="id790860"></a>
+<a name="id755604"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.matching_line_endings">Matching
         Line Endings</a>
       </h6>
@@ -1090,7 +1092,7 @@
         sequence, specifically it is identical to the expression <code class="literal">(?&gt;\x0D\x0A?|[\x0A-\x0C\x85\x{2028}\x{2029}])</code>.
       </p>
 <a name="boost_regex.syntax.perl_syntax.keeping_back_some_text"></a><h6>
-<a name="id790886"></a>
+<a name="id755630"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.keeping_back_some_text">Keeping
         back some text</a>
       </h6>
@@ -1105,7 +1107,7 @@
         This can be used to simulate variable width lookbehind assertions.
       </p>
 <a name="boost_regex.syntax.perl_syntax.any_other_escape"></a><h6>
-<a name="id790916"></a>
+<a name="id755660"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.any_other_escape">Any other
         escape</a>
       </h6>
@@ -1114,7 +1116,7 @@
         \@ matches a literal '@'.
       </p>
 <a name="boost_regex.syntax.perl_syntax.perl_extended_patterns"></a><h5>
-<a name="id790933"></a>
+<a name="id755677"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.perl_extended_patterns">Perl
         Extended Patterns</a>
       </h5>
@@ -1123,7 +1125,7 @@
         <code class="literal">(?</code>.
       </p>
 <a name="boost_regex.syntax.perl_syntax.named_subexpressions"></a><h6>
-<a name="id790955"></a>
+<a name="id755699"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.named_subexpressions">Named
         Subexpressions</a>
       </h6>
@@ -1145,14 +1147,14 @@
         format string for search and replace operations, or in the <a class="link" href="../ref/match_results.html" title="match_results"><code class="computeroutput"><span class="identifier">match_results</span></code></a> member functions.
       </p>
 <a name="boost_regex.syntax.perl_syntax.comments"></a><h6>
-<a name="id791050"></a>
+<a name="id755793"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.comments">Comments</a>
       </h6>
 <p>
         <code class="literal">(?# ... )</code> is treated as a comment, it's contents are ignored.
       </p>
 <a name="boost_regex.syntax.perl_syntax.modifiers"></a><h6>
-<a name="id791072"></a>
+<a name="id755816"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.modifiers">Modifiers</a>
       </h6>
 <p>
@@ -1166,7 +1168,7 @@
         pattern only.
       </p>
 <a name="boost_regex.syntax.perl_syntax.non_marking_groups"></a><h6>
-<a name="id791107"></a>
+<a name="id755851"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.non_marking_groups">Non-marking
         groups</a>
       </h6>
@@ -1175,7 +1177,7 @@
         an additional sub-expression.
       </p>
 <a name="boost_regex.syntax.perl_syntax.branch_reset"></a><h6>
-<a name="id791129"></a>
+<a name="id755873"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.branch_reset">Branch reset</a>
       </h6>
 <p>
@@ -1197,7 +1199,7 @@
 # 1            2         2  3        2     3     4
 </pre>
 <a name="boost_regex.syntax.perl_syntax.lookahead"></a><h6>
-<a name="id791166"></a>
+<a name="id755910"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.lookahead">Lookahead</a>
       </h6>
 <p>
@@ -1220,7 +1222,7 @@
         could be used to validate the password.
       </p>
 <a name="boost_regex.syntax.perl_syntax.lookbehind"></a><h6>
-<a name="id791240"></a>
+<a name="id756410"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.lookbehind">Lookbehind</a>
       </h6>
 <p>
@@ -1234,7 +1236,7 @@
         (pattern must be of fixed length).
       </p>
 <a name="boost_regex.syntax.perl_syntax.independent_sub_expressions"></a><h6>
-<a name="id791273"></a>
+<a name="id756442"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.independent_sub_expressions">Independent
         sub-expressions</a>
       </h6>
@@ -1247,7 +1249,7 @@
         no match is found at all.
       </p>
 <a name="boost_regex.syntax.perl_syntax.recursive_expressions"></a><h6>
-<a name="id791304"></a>
+<a name="id756474"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.recursive_expressions">Recursive
         Expressions</a>
       </h6>
@@ -1271,7 +1273,7 @@
         to the next sub-expression to be declared.
       </p>
 <a name="boost_regex.syntax.perl_syntax.conditional_expressions"></a><h6>
-<a name="id791401"></a>
+<a name="id756571"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.conditional_expressions">Conditional
         Expressions</a>
       </h6>
@@ -1319,7 +1321,7 @@
         </li>
 </ul></div>
 <a name="boost_regex.syntax.perl_syntax.operator_precedence"></a><h5>
-<a name="id791543"></a>
+<a name="id756712"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.operator_precedence">Operator
         precedence</a>
       </h5>
@@ -1354,7 +1356,7 @@
         </li>
 </ol></div>
 <a name="boost_regex.syntax.perl_syntax.what_gets_matched"></a><h4>
-<a name="id791633"></a>
+<a name="id756802"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.what_gets_matched">What gets
         matched</a>
       </h4>
@@ -1529,7 +1531,7 @@
 </tbody>
 </table></div>
 <a name="boost_regex.syntax.perl_syntax.variations"></a><h4>
-<a name="id792157"></a>
+<a name="id757160"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.variations">Variations</a>
       </h4>
 <p>
@@ -1538,7 +1540,7 @@
         and <code class="literal">JScript</code></a> are all synonyms for <code class="literal">perl</code>.
       </p>
 <a name="boost_regex.syntax.perl_syntax.options"></a><h4>
-<a name="id792204"></a>
+<a name="id757207"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.options">Options</a>
       </h4>
 <p>
@@ -1550,7 +1552,7 @@
         are to be applied.
       </p>
 <a name="boost_regex.syntax.perl_syntax.pattern_modifiers"></a><h4>
-<a name="id792252"></a>
+<a name="id757255"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.pattern_modifiers">Pattern
         Modifiers</a>
       </h4>
@@ -1562,7 +1564,7 @@
         and <code class="literal">no_mod_s</code></a>.
       </p>
 <a name="boost_regex.syntax.perl_syntax.references"></a><h4>
-<a name="id792305"></a>
+<a name="id757308"></a>
         <a class="link" href="perl_syntax.html#boost_regex.syntax.perl_syntax.references">References</a>
       </h4>
 <p>