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diff --git a/Help/command/string.rst b/Help/command/string.rst new file mode 100644 index 0000000..c191c63 --- /dev/null +++ b/Help/command/string.rst @@ -0,0 +1,152 @@ +string +------ + +String operations. + +:: + + string(REGEX MATCH <regular_expression> + <output variable> <input> [<input>...]) + string(REGEX MATCHALL <regular_expression> + <output variable> <input> [<input>...]) + string(REGEX REPLACE <regular_expression> + <replace_expression> <output variable> + <input> [<input>...]) + string(REPLACE <match_string> + <replace_string> <output variable> + <input> [<input>...]) + string(<MD5|SHA1|SHA224|SHA256|SHA384|SHA512> + <output variable> <input>) + string(COMPARE EQUAL <string1> <string2> <output variable>) + string(COMPARE NOTEQUAL <string1> <string2> <output variable>) + string(COMPARE LESS <string1> <string2> <output variable>) + string(COMPARE GREATER <string1> <string2> <output variable>) + string(ASCII <number> [<number> ...] <output variable>) + string(CONFIGURE <string1> <output variable> + [@ONLY] [ESCAPE_QUOTES]) + string(TOUPPER <string1> <output variable>) + string(TOLOWER <string1> <output variable>) + string(LENGTH <string> <output variable>) + string(SUBSTRING <string> <begin> <length> <output variable>) + string(STRIP <string> <output variable>) + string(RANDOM [LENGTH <length>] [ALPHABET <alphabet>] + [RANDOM_SEED <seed>] <output variable>) + string(FIND <string> <substring> <output variable> [REVERSE]) + string(TIMESTAMP <output variable> [<format string>] [UTC]) + string(MAKE_C_IDENTIFIER <input string> <output variable>) + +REGEX MATCH will match the regular expression once and store the match +in the output variable. + +REGEX MATCHALL will match the regular expression as many times as +possible and store the matches in the output variable as a list. + +REGEX REPLACE will match the regular expression as many times as +possible and substitute the replacement expression for the match in +the output. The replace expression may refer to paren-delimited +subexpressions of the match using \1, \2, ..., \9. Note that two +backslashes (\\1) are required in CMake code to get a backslash +through argument parsing. + +REPLACE will replace all occurrences of match_string in the input with +replace_string and store the result in the output. + +MD5, SHA1, SHA224, SHA256, SHA384, and SHA512 will compute a +cryptographic hash of the input string. + +COMPARE EQUAL/NOTEQUAL/LESS/GREATER will compare the strings and store +true or false in the output variable. + +ASCII will convert all numbers into corresponding ASCII characters. + +CONFIGURE will transform a string like CONFIGURE_FILE transforms a +file. + +TOUPPER/TOLOWER will convert string to upper/lower characters. + +LENGTH will return a given string's length. + +SUBSTRING will return a substring of a given string. If length is -1 +the remainder of the string starting at begin will be returned. + +STRIP will return a substring of a given string with leading and +trailing spaces removed. + +RANDOM will return a random string of given length consisting of +characters from the given alphabet. Default length is 5 characters +and default alphabet is all numbers and upper and lower case letters. +If an integer RANDOM_SEED is given, its value will be used to seed the +random number generator. + +FIND will return the position where the given substring was found in +the supplied string. If the REVERSE flag was used, the command will +search for the position of the last occurrence of the specified +substring. + +The following characters have special meaning in regular expressions: + +:: + + ^ Matches at beginning of input + $ Matches at end of input + . Matches any single character + [ ] Matches any character(s) inside the brackets + [^ ] Matches any character(s) not inside the brackets + - Inside brackets, specifies an inclusive range between + characters on either side e.g. [a-f] is [abcdef] + To match a literal - using brackets, make it the first + or the last character e.g. [+*/-] matches basic + mathematical operators. + * Matches preceding pattern zero or more times + + Matches preceding pattern one or more times + ? Matches preceding pattern zero or once only + | Matches a pattern on either side of the | + () Saves a matched subexpression, which can be referenced + in the REGEX REPLACE operation. Additionally it is saved + by all regular expression-related commands, including + e.g. if( MATCHES ), in the variables CMAKE_MATCH_(0..9). + +*, + and ? have higher precedence than concatenation. | has lower +precedence than concatenation. This means that the regular expression +"^ab+d$" matches "abbd" but not "ababd", and the regular expression +"^(ab|cd)$" matches "ab" but not "abd". + +TIMESTAMP will write a string representation of the current date +and/or time to the output variable. + +Should the command be unable to obtain a timestamp the output variable +will be set to the empty string "". + +The optional UTC flag requests the current date/time representation to +be in Coordinated Universal Time (UTC) rather than local time. + +The optional <format string> may contain the following format +specifiers: + +:: + + %d The day of the current month (01-31). + %H The hour on a 24-hour clock (00-23). + %I The hour on a 12-hour clock (01-12). + %j The day of the current year (001-366). + %m The month of the current year (01-12). + %M The minute of the current hour (00-59). + %S The second of the current minute. + 60 represents a leap second. (00-60) + %U The week number of the current year (00-53). + %w The day of the current week. 0 is Sunday. (0-6) + %y The last two digits of the current year (00-99) + %Y The current year. + +Unknown format specifiers will be ignored and copied to the output +as-is. + +If no explicit <format string> is given it will default to: + +:: + + %Y-%m-%dT%H:%M:%S for local time. + %Y-%m-%dT%H:%M:%SZ for UTC. + +MAKE_C_IDENTIFIER will write a string which can be used as an +identifier in C. |