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diff --git a/external-libs/pcre/doc/pcretest.txt b/external-libs/pcre/doc/pcretest.txt deleted file mode 100644 index 0e9cd138..00000000 --- a/external-libs/pcre/doc/pcretest.txt +++ /dev/null @@ -1,357 +0,0 @@ -PCRETEST(1) PCRETEST(1) - - - -NAME - pcretest - a program for testing Perl-compatible regular expressions. - -SYNOPSIS - pcretest [-d] [-i] [-m] [-o osize] [-p] [-t] [source] [destination] - - pcretest was written as a test program for the PCRE regular expression - library itself, but it can also be used for experimenting with regular - expressions. This document describes the features of the test program; - for details of the regular expressions themselves, see the pcrepattern - documentation. For details of PCRE and its options, see the pcreapi - documentation. - - -OPTIONS - - - -C Output the version number of the PCRE library, and all avail- - able information about the optional features that are - included, and then exit. - - -d Behave as if each regex had the /D modifier (see below); the - internal form is output after compilation. - - -i Behave as if each regex had the /I modifier; information - about the compiled pattern is given after compilation. - - -m Output the size of each compiled pattern after it has been - compiled. This is equivalent to adding /M to each regular - expression. For compatibility with earlier versions of - pcretest, -s is a synonym for -m. - - -o osize Set the number of elements in the output vector that is used - when calling PCRE to be osize. The default value is 45, which - is enough for 14 capturing subexpressions. The vector size - can be changed for individual matching calls by including \O - in the data line (see below). - - -p Behave as if each regex has /P modifier; the POSIX wrapper - API is used to call PCRE. None of the other options has any - effect when -p is set. - - -t Run each compile, study, and match many times with a timer, - and output resulting time per compile or match (in millisec- - onds). Do not set -t with -m, because you will then get the - size output 20000 times and the timing will be distorted. - - -DESCRIPTION - - If pcretest is given two filename arguments, it reads from the first - and writes to the second. If it is given only one filename argument, it - reads from that file and writes to stdout. Otherwise, it reads from - stdin and writes to stdout, and prompts for each line of input, using - "re>" to prompt for regular expressions, and "data>" to prompt for data - lines. - - The program handles any number of sets of input on a single input file. - Each set starts with a regular expression, and continues with any num- - ber of data lines to be matched against the pattern. - - Each line is matched separately and independently. If you want to do - multiple-line matches, you have to use the \n escape sequence in a sin- - gle line of input to encode the newline characters. The maximum length - of data line is 30,000 characters. - - An empty line signals the end of the data lines, at which point a new - regular expression is read. The regular expressions are given enclosed - in any non-alphameric delimiters other than backslash, for example - - /(a|bc)x+yz/ - - White space before the initial delimiter is ignored. A regular expres- - sion may be continued over several input lines, in which case the new- - line characters are included within it. It is possible to include the - delimiter within the pattern by escaping it, for example - - /abc\/def/ - - If you do so, the escape and the delimiter form part of the pattern, - but since delimiters are always non-alphameric, this does not affect - its interpretation. If the terminating delimiter is immediately fol- - lowed by a backslash, for example, - - /abc/\ - - then a backslash is added to the end of the pattern. This is done to - provide a way of testing the error condition that arises if a pattern - finishes with a backslash, because - - /abc\/ - - is interpreted as the first line of a pattern that starts with "abc/", - causing pcretest to read the next line as a continuation of the regular - expression. - - -PATTERN MODIFIERS - - The pattern may be followed by i, m, s, or x to set the PCRE_CASELESS, - PCRE_MULTILINE, PCRE_DOTALL, or PCRE_EXTENDED options, respectively. - For example: - - /caseless/i - - These modifier letters have the same effect as they do in Perl. There - are others that set PCRE options that do not correspond to anything in - Perl: /A, /E, /N, /U, and /X set PCRE_ANCHORED, PCRE_DOLLAR_ENDONLY, - PCRE_NO_AUTO_CAPTURE, PCRE_UNGREEDY, and PCRE_EXTRA respectively. - - Searching for all possible matches within each subject string can be - requested by the /g or /G modifier. After finding a match, PCRE is - called again to search the remainder of the subject string. The differ- - ence between /g and /G is that the former uses the startoffset argument - to pcre_exec() to start searching at a new point within the entire - string (which is in effect what Perl does), whereas the latter passes - over a shortened substring. This makes a difference to the matching - process if the pattern begins with a lookbehind assertion (including \b - or \B). - - If any call to pcre_exec() in a /g or /G sequence matches an empty - string, the next call is done with the PCRE_NOTEMPTY and PCRE_ANCHORED - flags set in order to search for another, non-empty, match at the same - point. If this second match fails, the start offset is advanced by - one, and the normal match is retried. This imitates the way Perl han- - dles such cases when using the /g modifier or the split() function. - - There are a number of other modifiers for controlling the way pcretest - operates. - - The /+ modifier requests that as well as outputting the substring that - matched the entire pattern, pcretest should in addition output the - remainder of the subject string. This is useful for tests where the - subject contains multiple copies of the same substring. - - The /L modifier must be followed directly by the name of a locale, for - example, - - /pattern/Lfr - - For this reason, it must be the last modifier letter. The given locale - is set, pcre_maketables() is called to build a set of character tables - for the locale, and this is then passed to pcre_compile() when compil- - ing the regular expression. Without an /L modifier, NULL is passed as - the tables pointer; that is, /L applies only to the expression on which - it appears. - - The /I modifier requests that pcretest output information about the - compiled expression (whether it is anchored, has a fixed first charac- - ter, and so on). It does this by calling pcre_fullinfo() after compil- - ing an expression, and outputting the information it gets back. If the - pattern is studied, the results of that are also output. - - The /D modifier is a PCRE debugging feature, which also assumes /I. It - causes the internal form of compiled regular expressions to be output - after compilation. If the pattern was studied, the information returned - is also output. - - The /S modifier causes pcre_study() to be called after the expression - has been compiled, and the results used when the expression is matched. - - The /M modifier causes the size of memory block used to hold the com- - piled pattern to be output. - - The /P modifier causes pcretest to call PCRE via the POSIX wrapper API - rather than its native API. When this is done, all other modifiers - except /i, /m, and /+ are ignored. REG_ICASE is set if /i is present, - and REG_NEWLINE is set if /m is present. The wrapper functions force - PCRE_DOLLAR_ENDONLY always, and PCRE_DOTALL unless REG_NEWLINE is set. - - The /8 modifier causes pcretest to call PCRE with the PCRE_UTF8 option - set. This turns on support for UTF-8 character handling in PCRE, pro- - vided that it was compiled with this support enabled. This modifier - also causes any non-printing characters in output strings to be printed - using the \x{hh...} notation if they are valid UTF-8 sequences. - - If the /? modifier is used with /8, it causes pcretest to call - pcre_compile() with the PCRE_NO_UTF8_CHECK option, to suppress the - checking of the string for UTF-8 validity. - - -CALLOUTS - - If the pattern contains any callout requests, pcretest's callout func- - tion will be called. By default, it displays the callout number, and - the start and current positions in the text at the callout time. For - example, the output - - --->pqrabcdef - 0 ^ ^ - - indicates that callout number 0 occurred for a match attempt starting - at the fourth character of the subject string, when the pointer was at - the seventh character. The callout function returns zero (carry on - matching) by default. - - Inserting callouts may be helpful when using pcretest to check compli- - cated regular expressions. For further information about callouts, see - the pcrecallout documentation. - - For testing the PCRE library, additional control of callout behaviour - is available via escape sequences in the data, as described in the fol- - lowing section. In particular, it is possible to pass in a number as - callout data (the default is zero). If the callout function receives a - non-zero number, it returns that value instead of zero. - - -DATA LINES - - Before each data line is passed to pcre_exec(), leading and trailing - whitespace is removed, and it is then scanned for \ escapes. Some of - these are pretty esoteric features, intended for checking out some of - the more complicated features of PCRE. If you are just testing "ordi- - nary" regular expressions, you probably don't need any of these. The - following escapes are recognized: - - \a alarm (= BEL) - \b backspace - \e escape - \f formfeed - \n newline - \r carriage return - \t tab - \v vertical tab - \nnn octal character (up to 3 octal digits) - \xhh hexadecimal character (up to 2 hex digits) - \x{hh...} hexadecimal character, any number of digits - in UTF-8 mode - \A pass the PCRE_ANCHORED option to pcre_exec() - \B pass the PCRE_NOTBOL option to pcre_exec() - \Cdd call pcre_copy_substring() for substring dd - after a successful match (any decimal number - less than 32) - \Cname call pcre_copy_named_substring() for substring - "name" after a successful match (name termin- - ated by next non alphanumeric character) - \C+ show the current captured substrings at callout - time - \C- do not supply a callout function - \C!n return 1 instead of 0 when callout number n is - reached - \C!n!m return 1 instead of 0 when callout number n is - reached for the nth time - \C*n pass the number n (may be negative) as callout - data - \Gdd call pcre_get_substring() for substring dd - after a successful match (any decimal number - less than 32) - \Gname call pcre_get_named_substring() for substring - "name" after a successful match (name termin- - ated by next non-alphanumeric character) - \L call pcre_get_substringlist() after a - successful match - \M discover the minimum MATCH_LIMIT setting - \N pass the PCRE_NOTEMPTY option to pcre_exec() - \Odd set the size of the output vector passed to - pcre_exec() to dd (any number of decimal - digits) - \S output details of memory get/free calls during matching - \Z pass the PCRE_NOTEOL option to pcre_exec() - \? pass the PCRE_NO_UTF8_CHECK option to - pcre_exec() - - If \M is present, pcretest calls pcre_exec() several times, with dif- - ferent values in the match_limit field of the pcre_extra data struc- - ture, until it finds the minimum number that is needed for pcre_exec() - to complete. This number is a measure of the amount of recursion and - backtracking that takes place, and checking it out can be instructive. - For most simple matches, the number is quite small, but for patterns - with very large numbers of matching possibilities, it can become large - very quickly with increasing length of subject string. - - When \O is used, it may be higher or lower than the size set by the -O - option (or defaulted to 45); \O applies only to the call of pcre_exec() - for the line in which it appears. - - A backslash followed by anything else just escapes the anything else. - If the very last character is a backslash, it is ignored. This gives a - way of passing an empty line as data, since a real empty line termi- - nates the data input. - - If /P was present on the regex, causing the POSIX wrapper API to be - used, only 0 causing REG_NOTBOL and REG_NOTEOL to be passed to - regexec() respectively. - - The use of \x{hh...} to represent UTF-8 characters is not dependent on - the use of the /8 modifier on the pattern. It is recognized always. - There may be any number of hexadecimal digits inside the braces. The - result is from one to six bytes, encoded according to the UTF-8 rules. - - -OUTPUT FROM PCRETEST - - When a match succeeds, pcretest outputs the list of captured substrings - that pcre_exec() returns, starting with number 0 for the string that - matched the whole pattern. Here is an example of an interactive - pcretest run. - - $ pcretest - PCRE version 4.00 08-Jan-2003 - - re> /^abc(\d+)/ - data> abc123 - 0: abc123 - 1: 123 - data> xyz - No match - - If the strings contain any non-printing characters, they are output as - \0x escapes, or as \x{...} escapes if the /8 modifier was present on - the pattern. If the pattern has the /+ modifier, then the output for - substring 0 is followed by the the rest of the subject string, identi- - fied by "0+" like this: - - re> /cat/+ - data> cataract - 0: cat - 0+ aract - - If the pattern has the /g or /G modifier, the results of successive - matching attempts are output in sequence, like this: - - re> /\Bi(\w\w)/g - data> Mississippi - 0: iss - 1: ss - 0: iss - 1: ss - 0: ipp - 1: pp - - "No match" is output only if the first match attempt fails. - - If any of the sequences \C, \G, or \L are present in a data line that - is successfully matched, the substrings extracted by the convenience - functions are output with C, G, or L after the string number instead of - a colon. This is in addition to the normal full list. The string length - (that is, the return from the extraction function) is given in paren- - theses after each string for \C and \G. - - Note that while patterns can be continued over several lines (a plain - ">" prompt is used for continuations), data lines may not. However new- - lines can be included in data by means of the \n escape. - - -AUTHOR - - Philip Hazel <ph10@cam.ac.uk> - University Computing Service, - Cambridge CB2 3QG, England. - -Last updated: 09 December 2003 -Copyright (c) 1997-2003 University of Cambridge. |