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diff --git a/ext/pcre/pcrelib/doc/pcretest.txt b/ext/pcre/pcrelib/doc/pcretest.txt deleted file mode 100644 index add2979f14..0000000000 --- a/ext/pcre/pcrelib/doc/pcretest.txt +++ /dev/null @@ -1,246 +0,0 @@ -The pcretest program --------------------- - -This program is intended for testing PCRE, but it can also be used for -experimenting with regular expressions. - -If it 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 number of data -lines to be matched against the pattern. 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 expression may -be continued over several input lines, in which case the newline characters are -included within it. See the test input files in the testdata directory for many -examples. 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 followed 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 which set PCRE options that do not correspond to anything in Perl: /A, -/E, and /X set PCRE_ANCHORED, PCRE_DOLLAR_ENDONLY, 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 difference 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 handles 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 compiling 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 character, and so on). It -does this by calling pcre_fullinfo() after compiling 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. - -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 compiled -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 the (currently incomplete) support for UTF-8 character handling -in PCRE, provided 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. - - -DATA LINES ----------- - -Before each data line is passed to pcre_exec(), leading and trailing whitespace -is removed, and it is then scanned for \ escapes. The following 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 UTF-8 character - - \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) - \Gdd call pcre_get_substring() for substring dd after a successful - match (any decimal number less than 32) - \L call pcre_get_substringlist() after a successful match - \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) - \Z pass the PCRE_NOTEOL option to pcre_exec() - -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 terminates the data input. - -If /P was present on the regex, causing the POSIX wrapper API to be used, only -\B, and \Z have any effect, 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 2.06 08-Jun-1999 - - 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, identified 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 \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 parentheses 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 newlines can be -included in data by means of the \n escape. - - -COMMAND LINE OPTIONS --------------------- - -If the -p option is given to pcretest, it is equivalent to adding /P to each -regular expression: the POSIX wrapper API is used to call PCRE. None of the -following flags has any effect in this case. - -If the option -d is given to pcretest, it is equivalent to adding /D to each -regular expression: the internal form is output after compilation. - -If the option -i is given to pcretest, it is equivalent to adding /I to each -regular expression: information about the compiled pattern is given after -compilation. - -If the option -m is given to pcretest, it outputs the size of each compiled -pattern after it has been compiled. It is equivalent to adding /M to each -regular expression. For compatibility with earlier versions of pcretest, -s is -a synonym for -m. - -If the -t option is given, each compile, study, and match is run 20000 times -while being timed, and the resulting time per compile or match is output in -milliseconds. Do not set -t with -m, because you will then get the size output -20000 times and the timing will be distorted. If you want to change the number -of repetitions used for timing, edit the definition of LOOPREPEAT at the top of -pcretest.c - -Philip Hazel <ph10@cam.ac.uk> -August 2000 |