Regex indexof short

Benchmark created by Peter van der Zee on August 21, 2011

Description

Preparation HTML

<script>
  String.prototype.regexIndexOf_1 = function(regexBody, start) {
        if (typeof regexBody != 'string') regexBody = regexBody.toString().slice(1,-1); // if not a string, then convert regex to string (but only take body)
        if (typeof start != 'number' || start < 0) start = 0;
        for (var i=start,len=this.length; i<len; ++i) {
                if (new RegExp('^.{'+i+'}'+regexBody, '').test(this)) {
                        return i;
                }
        }
        return -1;
  };
  
  String.prototype.regexIndexOf_2 = function(regexBody, start) {
        if (typeof regexBody != 'string') regexBody = regexBody.toString().slice(1,-1);
        if (typeof start != 'number' || start < 0) start = 0;
        for (var i=start,len=this.length; i<len; ++i) {
                if (RegExp('^.{'+i+'}'+regexBody, '').test(this)) {
                        return i;
                }
        }
        return -1;
  };
  
  // lastIndexOf is easy: just make the .* greedy
  String.prototype.regexIndexOf_3 = function(regexBody, pos) {
        if (typeof regexBody != 'string') regexBody = regexBody.toString().slice(1,-1); // if not a string, then convert regex to string (but only take body)
        var startIgnore = '';
        if (typeof pos != 'number' || pos < 0) pos = 0;
        else startIgnore = '.{'+pos+'}';
        var result = new RegExp('^'+startIgnore+'(.*?)'+regexBody, '').exec(this);
        if (result && result[1]) return pos + String(result[1]).length;
        return -1;
  };
  
  // slipsum.com
  var testString = "My money's in that office, right? If she start giving me some bullshit about it ain't there, and we got to go someplace else and get it, I'm gonna shoot you in the head then and there. Then I'm gonna shoot that bitch in the kneecaps, find out where my goddamn money is. She gonna tell me too. Hey, look at me when I'm talking to you, motherfucker. You listen: we go in there, and that nigga Winston or anybody else is in there, you the first motherfucker to get shot. You understand?";
</script>

Test runner

testString.regexIndexOf_1('Winston');

testString.regexIndexOf_2('Winston');

testString.regexIndexOf_1('Winston',2);

testString.regexIndexOf_3('Winston');

testString.regexIndexOf_3('Winston',2);

testString.search('Winston');

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.

• Revision 1: published by Peter van der Zee on August 21, 2011