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diff --git a/libs/Pcre16/docs/doc/pcrecpp.3 b/libs/Pcre16/docs/doc/pcrecpp.3 deleted file mode 100644 index fbddd86ab3..0000000000 --- a/libs/Pcre16/docs/doc/pcrecpp.3 +++ /dev/null @@ -1,348 +0,0 @@ -.TH PCRECPP 3 "08 January 2012" "PCRE 8.30" -.SH NAME -PCRE - Perl-compatible regular expressions. -.SH "SYNOPSIS OF C++ WRAPPER" -.rs -.sp -.B #include <pcrecpp.h> -. -.SH DESCRIPTION -.rs -.sp -The C++ wrapper for PCRE was provided by Google Inc. Some additional -functionality was added by Giuseppe Maxia. This brief man page was constructed -from the notes in the \fIpcrecpp.h\fP file, which should be consulted for -further details. Note that the C++ wrapper supports only the original 8-bit -PCRE library. There is no 16-bit or 32-bit support at present. -. -. -.SH "MATCHING INTERFACE" -.rs -.sp -The "FullMatch" operation checks that supplied text matches a supplied pattern -exactly. If pointer arguments are supplied, it copies matched sub-strings that -match sub-patterns into them. -.sp - Example: successful match - pcrecpp::RE re("h.*o"); - re.FullMatch("hello"); -.sp - Example: unsuccessful match (requires full match): - pcrecpp::RE re("e"); - !re.FullMatch("hello"); -.sp - Example: creating a temporary RE object: - pcrecpp::RE("h.*o").FullMatch("hello"); -.sp -You can pass in a "const char*" or a "string" for "text". The examples below -tend to use a const char*. You can, as in the different examples above, store -the RE object explicitly in a variable or use a temporary RE object. The -examples below use one mode or the other arbitrarily. Either could correctly be -used for any of these examples. -.P -You must supply extra pointer arguments to extract matched subpieces. -.sp - Example: extracts "ruby" into "s" and 1234 into "i" - int i; - string s; - pcrecpp::RE re("(\e\ew+):(\e\ed+)"); - re.FullMatch("ruby:1234", &s, &i); -.sp - Example: does not try to extract any extra sub-patterns - re.FullMatch("ruby:1234", &s); -.sp - Example: does not try to extract into NULL - re.FullMatch("ruby:1234", NULL, &i); -.sp - Example: integer overflow causes failure - !re.FullMatch("ruby:1234567891234", NULL, &i); -.sp - Example: fails because there aren't enough sub-patterns: - !pcrecpp::RE("\e\ew+:\e\ed+").FullMatch("ruby:1234", &s); -.sp - Example: fails because string cannot be stored in integer - !pcrecpp::RE("(.*)").FullMatch("ruby", &i); -.sp -The provided pointer arguments can be pointers to any scalar numeric -type, or one of: -.sp - string (matched piece is copied to string) - StringPiece (StringPiece is mutated to point to matched piece) - T (where "bool T::ParseFrom(const char*, int)" exists) - NULL (the corresponding matched sub-pattern is not copied) -.sp -The function returns true iff all of the following conditions are satisfied: -.sp - a. "text" matches "pattern" exactly; -.sp - b. The number of matched sub-patterns is >= number of supplied - pointers; -.sp - c. The "i"th argument has a suitable type for holding the - string captured as the "i"th sub-pattern. If you pass in - void * NULL for the "i"th argument, or a non-void * NULL - of the correct type, or pass fewer arguments than the - number of sub-patterns, "i"th captured sub-pattern is - ignored. -.sp -CAVEAT: An optional sub-pattern that does not exist in the matched -string is assigned the empty string. Therefore, the following will -return false (because the empty string is not a valid number): -.sp - int number; - pcrecpp::RE::FullMatch("abc", "[a-z]+(\e\ed+)?", &number); -.sp -The matching interface supports at most 16 arguments per call. -If you need more, consider using the more general interface -\fBpcrecpp::RE::DoMatch\fP. See \fBpcrecpp.h\fP for the signature for -\fBDoMatch\fP. -.P -NOTE: Do not use \fBno_arg\fP, which is used internally to mark the end of a -list of optional arguments, as a placeholder for missing arguments, as this can -lead to segfaults. -. -. -.SH "QUOTING METACHARACTERS" -.rs -.sp -You can use the "QuoteMeta" operation to insert backslashes before all -potentially meaningful characters in a string. The returned string, used as a -regular expression, will exactly match the original string. -.sp - Example: - string quoted = RE::QuoteMeta(unquoted); -.sp -Note that it's legal to escape a character even if it has no special meaning in -a regular expression -- so this function does that. (This also makes it -identical to the perl function of the same name; see "perldoc -f quotemeta".) -For example, "1.5-2.0?" becomes "1\e.5\e-2\e.0\e?". -. -.SH "PARTIAL MATCHES" -.rs -.sp -You can use the "PartialMatch" operation when you want the pattern -to match any substring of the text. -.sp - Example: simple search for a string: - pcrecpp::RE("ell").PartialMatch("hello"); -.sp - Example: find first number in a string: - int number; - pcrecpp::RE re("(\e\ed+)"); - re.PartialMatch("x*100 + 20", &number); - assert(number == 100); -. -. -.SH "UTF-8 AND THE MATCHING INTERFACE" -.rs -.sp -By default, pattern and text are plain text, one byte per character. The UTF8 -flag, passed to the constructor, causes both pattern and string to be treated -as UTF-8 text, still a byte stream but potentially multiple bytes per -character. In practice, the text is likelier to be UTF-8 than the pattern, but -the match returned may depend on the UTF8 flag, so always use it when matching -UTF8 text. For example, "." will match one byte normally but with UTF8 set may -match up to three bytes of a multi-byte character. -.sp - Example: - pcrecpp::RE_Options options; - options.set_utf8(); - pcrecpp::RE re(utf8_pattern, options); - re.FullMatch(utf8_string); -.sp - Example: using the convenience function UTF8(): - pcrecpp::RE re(utf8_pattern, pcrecpp::UTF8()); - re.FullMatch(utf8_string); -.sp -NOTE: The UTF8 flag is ignored if pcre was not configured with the - --enable-utf8 flag. -. -. -.SH "PASSING MODIFIERS TO THE REGULAR EXPRESSION ENGINE" -.rs -.sp -PCRE defines some modifiers to change the behavior of the regular expression -engine. The C++ wrapper defines an auxiliary class, RE_Options, as a vehicle to -pass such modifiers to a RE class. Currently, the following modifiers are -supported: -.sp - modifier description Perl corresponding -.sp - PCRE_CASELESS case insensitive match /i - PCRE_MULTILINE multiple lines match /m - PCRE_DOTALL dot matches newlines /s - PCRE_DOLLAR_ENDONLY $ matches only at end N/A - PCRE_EXTRA strict escape parsing N/A - PCRE_EXTENDED ignore white spaces /x - PCRE_UTF8 handles UTF8 chars built-in - PCRE_UNGREEDY reverses * and *? N/A - PCRE_NO_AUTO_CAPTURE disables capturing parens N/A (*) -.sp -(*) Both Perl and PCRE allow non capturing parentheses by means of the -"?:" modifier within the pattern itself. e.g. (?:ab|cd) does not -capture, while (ab|cd) does. -.P -For a full account on how each modifier works, please check the -PCRE API reference page. -.P -For each modifier, there are two member functions whose name is made -out of the modifier in lowercase, without the "PCRE_" prefix. For -instance, PCRE_CASELESS is handled by -.sp - bool caseless() -.sp -which returns true if the modifier is set, and -.sp - RE_Options & set_caseless(bool) -.sp -which sets or unsets the modifier. Moreover, PCRE_EXTRA_MATCH_LIMIT can be -accessed through the \fBset_match_limit()\fP and \fBmatch_limit()\fP member -functions. Setting \fImatch_limit\fP to a non-zero value will limit the -execution of pcre to keep it from doing bad things like blowing the stack or -taking an eternity to return a result. A value of 5000 is good enough to stop -stack blowup in a 2MB thread stack. Setting \fImatch_limit\fP to zero disables -match limiting. Alternatively, you can call \fBmatch_limit_recursion()\fP -which uses PCRE_EXTRA_MATCH_LIMIT_RECURSION to limit how much PCRE -recurses. \fBmatch_limit()\fP limits the number of matches PCRE does; -\fBmatch_limit_recursion()\fP limits the depth of internal recursion, and -therefore the amount of stack that is used. -.P -Normally, to pass one or more modifiers to a RE class, you declare -a \fIRE_Options\fP object, set the appropriate options, and pass this -object to a RE constructor. Example: -.sp - RE_Options opt; - opt.set_caseless(true); - if (RE("HELLO", opt).PartialMatch("hello world")) ... -.sp -RE_options has two constructors. The default constructor takes no arguments and -creates a set of flags that are off by default. The optional parameter -\fIoption_flags\fP is to facilitate transfer of legacy code from C programs. -This lets you do -.sp - RE(pattern, - RE_Options(PCRE_CASELESS|PCRE_MULTILINE)).PartialMatch(str); -.sp -However, new code is better off doing -.sp - RE(pattern, - RE_Options().set_caseless(true).set_multiline(true)) - .PartialMatch(str); -.sp -If you are going to pass one of the most used modifiers, there are some -convenience functions that return a RE_Options class with the -appropriate modifier already set: \fBCASELESS()\fP, \fBUTF8()\fP, -\fBMULTILINE()\fP, \fBDOTALL\fP(), and \fBEXTENDED()\fP. -.P -If you need to set several options at once, and you don't want to go through -the pains of declaring a RE_Options object and setting several options, there -is a parallel method that give you such ability on the fly. You can concatenate -several \fBset_xxxxx()\fP member functions, since each of them returns a -reference to its class object. For example, to pass PCRE_CASELESS, -PCRE_EXTENDED, and PCRE_MULTILINE to a RE with one statement, you may write: -.sp - RE(" ^ xyz \e\es+ .* blah$", - RE_Options() - .set_caseless(true) - .set_extended(true) - .set_multiline(true)).PartialMatch(sometext); -.sp -. -. -.SH "SCANNING TEXT INCREMENTALLY" -.rs -.sp -The "Consume" operation may be useful if you want to repeatedly -match regular expressions at the front of a string and skip over -them as they match. This requires use of the "StringPiece" type, -which represents a sub-range of a real string. Like RE, StringPiece -is defined in the pcrecpp namespace. -.sp - Example: read lines of the form "var = value" from a string. - string contents = ...; // Fill string somehow - pcrecpp::StringPiece input(contents); // Wrap in a StringPiece -.sp - string var; - int value; - pcrecpp::RE re("(\e\ew+) = (\e\ed+)\en"); - while (re.Consume(&input, &var, &value)) { - ...; - } -.sp -Each successful call to "Consume" will set "var/value", and also -advance "input" so it points past the matched text. -.P -The "FindAndConsume" operation is similar to "Consume" but does not -anchor your match at the beginning of the string. For example, you -could extract all words from a string by repeatedly calling -.sp - pcrecpp::RE("(\e\ew+)").FindAndConsume(&input, &word) -. -. -.SH "PARSING HEX/OCTAL/C-RADIX NUMBERS" -.rs -.sp -By default, if you pass a pointer to a numeric value, the -corresponding text is interpreted as a base-10 number. You can -instead wrap the pointer with a call to one of the operators Hex(), -Octal(), or CRadix() to interpret the text in another base. The -CRadix operator interprets C-style "0" (base-8) and "0x" (base-16) -prefixes, but defaults to base-10. -.sp - Example: - int a, b, c, d; - pcrecpp::RE re("(.*) (.*) (.*) (.*)"); - re.FullMatch("100 40 0100 0x40", - pcrecpp::Octal(&a), pcrecpp::Hex(&b), - pcrecpp::CRadix(&c), pcrecpp::CRadix(&d)); -.sp -will leave 64 in a, b, c, and d. -. -. -.SH "REPLACING PARTS OF STRINGS" -.rs -.sp -You can replace the first match of "pattern" in "str" with "rewrite". -Within "rewrite", backslash-escaped digits (\e1 to \e9) can be -used to insert text matching corresponding parenthesized group -from the pattern. \e0 in "rewrite" refers to the entire matching -text. For example: -.sp - string s = "yabba dabba doo"; - pcrecpp::RE("b+").Replace("d", &s); -.sp -will leave "s" containing "yada dabba doo". The result is true if the pattern -matches and a replacement occurs, false otherwise. -.P -\fBGlobalReplace\fP is like \fBReplace\fP except that it replaces all -occurrences of the pattern in the string with the rewrite. Replacements are -not subject to re-matching. For example: -.sp - string s = "yabba dabba doo"; - pcrecpp::RE("b+").GlobalReplace("d", &s); -.sp -will leave "s" containing "yada dada doo". It returns the number of -replacements made. -.P -\fBExtract\fP is like \fBReplace\fP, except that if the pattern matches, -"rewrite" is copied into "out" (an additional argument) with substitutions. -The non-matching portions of "text" are ignored. Returns true iff a match -occurred and the extraction happened successfully; if no match occurs, the -string is left unaffected. -. -. -.SH AUTHOR -.rs -.sp -.nf -The C++ wrapper was contributed by Google Inc. -Copyright (c) 2007 Google Inc. -.fi -. -. -.SH REVISION -.rs -.sp -.nf -Last updated: 08 January 2012 -.fi |