Subject: [Boost-commit] svn:boost r52169 - trunk/libs/spirit/doc/reference/lex
From: jamin.hanson_at_[hidden]
Date: 2009-04-04 09:56:39
Author: ben_hanson
Date: 2009-04-04 09:56:39 EDT (Sat, 04 Apr 2009)
New Revision: 52169
URL: http://svn.boost.org/trac/boost/changeset/52169
Log:
regex table
Text files modified:
trunk/libs/spirit/doc/reference/lex/lexer.qbk | 68 ++++++++++++++++++++++++++++++++++++++++
1 files changed, 68 insertions(+), 0 deletions(-)
Modified: trunk/libs/spirit/doc/reference/lex/lexer.qbk
==============================================================================
--- trunk/libs/spirit/doc/reference/lex/lexer.qbk (original)
+++ trunk/libs/spirit/doc/reference/lex/lexer.qbk 2009-04-04 09:56:39 EDT (Sat, 04 Apr 2009)
@@ -7,4 +7,72 @@
===============================================================================/]
[section Lexer]
+[table Regular expressions support
+ [[Expression] [Meaning]]
+ [[`x`] [Match any character `x`]]
+ [[`.`] [Match any except newline (or optionally *any* character)]]
+ [[`[xyz]`] [A character class; in this case matches `x`, `y` or `z`]]
+ [[`[abj-oZ]`] [A character class with a range in it; matches `a`, `b` any
+ letter from `j` through `o` or a `Z`]]
+ [[`[^A-Z]`] [A negated character class i.e. any character but those in
+ the class. In this case, any character except an uppercase
+ letter]]
+ [[`r*`] [Zero or more r's (greedy), where r is any regular expression]]
+ [[`r*?`] [Zero or more r's (abstemious), where r is any regular expression]]
+ [[`r+`] [One or more r's (greedy)]]
+ [[`r+?`] [One or more r's (abstemious)]]
+ [[`r?`] [Zero or one r's (greedy), i.e. optional]]
+ [[`r??`] [Zero or one r's (abstemious), i.e. optional]]
+ [[`r{2,5}`] [Anywhere between two and five r's (greedy)]]
+ [[`r{2,5}?`] [Anywhere between two and five r's (abstemious)]]
+ [[`r{2,}`] [Two or more r's (greedy)]]
+ [[`r{2,}?`] [Two or more r's (abstemious)]]
+ [[`r{4}`] [Exactly four r's]]
+ [[`{NAME}`] [The macro `NAME` (see below)]]
+ [[`"[xyz]\"foo"`] [The literal string `[xyz]\"foo`]]
+ [[`\X`] [If X is `a`, `b`, `e`, `n`, `r`, `f`, `t`, `v` then the
+ ANSI-C interpretation of `\x`. Otherwise a literal `X`
+ (used to escape operators such as `*`)]]
+ [[`\0`] [A NUL character (ASCII code 0)]]
+ [[`\123`] [The character with octal value 123]]
+ [[`\x2a`] [The character with hexadecimal value 2a]]
+ [[`\cX`] [A named control character `X`.]]
+ [[`\d`] [A shortcut for `[0-9]`]]
+ [[`\D`] [A shortcut for `[^0-9]`]]
+ [[`\s`] [A shortcut for `[\x20\t\n\r\f\v]`]]
+ [[`\S`] [A shortcut for `[^\x20\t\n\r\f\v]`]]
+ [[`\w`] [A shortcut for `[a-zA-Z0-9_]`]]
+ [[`\W`] [A shortcut for `[^a-zA-Z0-9_]`]]
+ [[`(r)`] [Match an `r`; parenthesis are used to override precedence
+ (see below)]]
+ [[`(?r-s:pattern)`] [apply option 'r' and omit option 's' while interpreting pattern.
+Options may be zero or more of the characters 'i' or 's'.
+'i' means case-insensitive. '-i' means case-sensitive.
+'s' alters the meaning of the '.' syntax to match any single character whatsoever.
+'-s' alters the meaning of '.' to match any character except '`\n`'.]]
+ [[`rs`] [The regular expression `r` followed by the regular
+ expression `s` (a sequence)]]
+ [[`r|s`] [Either an `r` or and `s`]]
+ [[`^r`] [An `r` but only at the beginning of a line (i.e. when just
+ starting to scan, or right after a newline has been
+ scanned)]]
+ [[`r`$] [An `r` but only at the end of a line (i.e. just before a
+ newline)]]
+]
+
+[note POSIX character classes are not currently supported, due to performance issues
+when creating them in wide character mode.]
+[br][h1 Regular Expression Precedence]
+
+* `rs` has highest precedence
+* `r*` has next highest (`+`, `?`, `{n,m}` have the same precedence as `*`)
+* `r|s` has the lowest precedence
+
+[h1 Macros]
+
+Regular expressions can be given a name and referred to in rules using the
+syntax `{NAME}` where `NAME` is the name you have given to the macro. A macro
+name can be at most 30 characters long and must start with a `_` or a letter.
+Subsequent characters can be `_`, `-`, a letter or a decimal digit.
+Use the `rules::add_macro()` method to define a macro.
[endsect]