JavaScript function I wrote to parse "and" and "or" into proper regex for use with Datatables.

datatablesParser.js

// QUnit tests.
 
// test("datatables parser", function() {
//     equal(datatablesParser("austin"), "austin");
//     equal(datatablesParser("houston or austin"), "houston|austin");
//     equal(datatablesParser("houston and austin or dallas"), "^(?=.*?\\bhouston\\b)(?=.*?\\baustin\\b).*$|^(?=.*?\\bdallas\\b).*$");
//     equal(datatablesParser("houston and austin or dallas and austin"), "^(?=.*?\\bhouston\\b)(?=.*?\\baustin\\b).*$|^(?=.*?\\bdallas\\b)(?=.*?\\baustin\\b).*$");
//     equal(datatablesParser("houston or austin or dallas"), "houston|austin|dallas");
// });
 
function datatablesParser(string) {
 
    alphastring = string;
    orstrings = [];
 
    // Descend into orland
    if (alphastring.match(/ [oO][rR] /) && alphastring.match(/ [oO][rR] /).index > -1) {
        while (string.match(/ [oO][rR] /)) {
            orstrings.push(string.substr(0, string.match(/ [oO][rR] /).index));
            string = string.substr(string.match(/ [oO][rR] /).index + 4);
        }
        orstrings.push(string);
    } else {
        orstrings = [string];
    }
 
    // Descend into andland
    if (alphastring.match(/ [aA][nN][dD] /) && alphastring.match(/ [aA][nN][dD] /).index > -1) {
        andstrings = [];
        for (var i = 0, len = orstrings.length; i < len; i++) {
            andstrings.push("^");
            while (orstrings[i].match(/ [aA][nN][dD] /)) {
                andstrings.push("(?=.*?\\b" + orstrings[i].substr(0, orstrings[i].match(/ [aA][nN][dD] /).index) + "\\b)");
                orstrings[i] = orstrings[i].substr(orstrings[i].match(/ [aA][nN][dD] /).index + 5);
            }
            andstrings.push("(?=.*?\\b" + orstrings[i] + "\\b)");
            andstrings.push(".*$");
            if (i != len - 1) {
                andstrings.push("|");
            }
        }
        return andstrings.join("");
    } else {
        omegastring = "";
        for (var i = 0, len = orstrings.length; i < len; i++) {
            omegastring += orstrings[i];
            if (i != len - 1) {
                omegastring += "|";
            }
        }
        return omegastring;
    }
 
}