Semiconductor & Computer Engineering
$replace Performs search/replace on text strings.
Synopsis
$replace( String, Searchstring1,Replacestring1 [,Searchstring2,Replacestring2 [ , ... ] ] )
Parameters
- string Text string that's the target of the search/replace
- SearchString 1st Search String
- ReplaceString Replacement string for all matches of SearchString1.
- Note: Excluding the target String, there must be an even number of search/replace parameters, even if any of them are $null. $replace(test,1) is an error but $replace(test,1,) is not. The number of search/replace pairs is limited only by the 4150 limit for the entire command.
- Note: The search is case-insensitive unless you use the case-sensitive equivalent $replacecs. $replacex also does search/replace, but searches in a different way.
Properties
None
Notes
If your search term contains a comma or parenthesis you must either use $chr(44) $chr(40) $chr(41) or place the term within a %variable.
Depending on which kind of search/replace you need, you can use either $replace or $replacex, their case-sensitive equivalents $replacecs or $replacexcs, or if you need regular expressions use $regsub or $regsubex.
$replace does a search/replace of a string using the first pair of search/replace strings, possibly doing multiple replacements. As it makes each replacement, the pointer is moved to the character following that replacement before continuing the search for another replacement using that same search term, until it reaches the end of the string. As long as there are additional pairs of search/replace strings, it uses the string modified by the prior search/replace pair as the target for search/replace using that next pair of parameters.
In effect, these are the same thing:
$replace( string,search1,replace1,search2,replace2 ) $replace( $replace(string,search1,replace1) ,search2,replace2)
$replacex does the search/replace differently. It begins with the 1st character of the original string, then tries each search/replace pair in left-to-right order until it finds a match. If no search/replace pair affects the 1st character, it moves the pointer to the next character. If there is a search/replace which affects the 1st character, it makes the replacement then sets the pointer at the character following that replacement. (The earliest character not yet involved in a search/replace) It then repeats the same search/replace rules at the new pointer's position, then continues repeating until it reaches the end of the string.
Examples
//echo -a $replace(Abcdabcd, a,b, a,c ) The 2nd pair does nothing because the first pair replaced all the a's with b's. Search is case-insensitive so both 'A' and 'a' match against 'a'. result: bbcdbbcd //var %string $chr(233) , %search $upper(%string) | echo -a $replace( %string , %search ,x) result: é case-sensitive applies only to a-z A-Z ranges, and does not apply the same rules as $upper and $lower. //echo -a $replace(abcdabcd, a,b ,b,c ) The 1st pair changes the string to bbcdbbcd The 2nd pair changes the modified string, changing all the b's into c's result: cccdcccd //echo -a $replace(abcdabcd, a,aa, a,x) The 1st pair changes each 'a' into 'aa', modifying string to aabcdaabcd The 2nd pair changes the modified string, changing the 4 'a' strings into 'x' strings. result: xxbcdxxbcd //echo -a $replace(abcdabcd, a,x, a,aa) With the search pairs in the opposite order, the first pair changes string to xbcdxbcd The 2nd pair does nothing because there are no 'a' strings in the modified string. //echo -a $replace( 1234, 1,2, 2,3, 3,4 ) result: 4444 The 1st search pair changes all '1' into '2', modifying string to 2234 The 2nd search pair changes all '2' into '3', modifying again to 3334 The 2nd search pair changes all '3' into '4', modifying again to 4444 //echo -a $replacex(1234, 1,2, 2,3, 3,4 ) result: 2344 The 1st match against the 1st character replaces the '1' with '2', moving the pointer to the '2' following the match. The 1st match against that new position replaces that '2' with 3, moving the pointer to the '3' following the match. The 1st match against that new position replaces that '3' with '4', moving the pointer to the '4' following the match. There are no more replacements, leaving the string as 2344. //echo -a $replace(aaaaaa,aa,a) result: aaa The replacement strings do not become part of the match string for that same search/replace pair. //echo -a $replace( aaaaaa,aa,a,aa,a) result: aa The 2nd pair sees the modified 'aaa' string and finds only 1 match. //echo -a $replacex(aaaaaa,aa,a,aa,a) result: aaa The identical 2nd pair never has a chance to match anything because the first pair always matches anything the 2nd could match before the pointer moves forward. //echo -a $replace(aaabbb,ab,) result: aabb Removes the 'ab' at position 3 (replaces 'ab' with $null), to make the string be 'aabb' and set the cursor at the character following the match. It makes no more replacements because there are no more 'ab' strings beginning at the new position. //echo -a $replace(aaabbb,,ab) result: aaabbb Unlike $regsub, if searchstring is $null, no change is made. //echo -a $replace(red fred red,red,x) replaces all 'red' strings with 'x' result: x fx x //echo -a $replace(red fred red,red $+ $chr(32) ,x) replaces only when 'red' is followed by a space result: xfxred //echo -a $replace(red fred red,$chr(32) $+ red,x) replaces only when 'red' is preceded by a space result: red fredx $replace is faster than $regsub for simple search/replace, but for many pairs it can become slower. Removing punctuation by replacing them with spaces: //var %sp $chr(32) | tokenize 32 $me $+ !?,*() | var %string $replace($1-,$chr(44),%sp,.,%sp,',%sp,',%sp,?,%sp,*,%sp,$chr(40),%sp,$chr(41),%sp ,!,%sp,;,%sp,:,%sp) | echo -a $1- / $istok(%string,$me,32)
Compatibility
Added: mIRC v4.52
Added on: 06 Jul 1996
Note: Unless otherwise stated, this was the date of original functionality.
Further enhancements may have been made in later versions.