Grammalecte  jsex_regex.js at [b32cdfdbe2]

File gc_core/js/jsex_regex.js artifact 35ff67872c part of check-in b32cdfdbe2

// regex

RegExp.prototype._exec2 = function (sText, aGroupsPos, aNegLookBefore=null) {
    let m;
    while ((m = this.exec(sText)) !== null) {
        // we have to iterate over sText here too
        // because first match doesn’t imply it’s a valid match according to negative lookbefore assertions,
        // and even if first match is finally invalid, it doesn’t mean the following eligible matchs would be invalid too.
        if (aNegLookBefore !== null) {
            // check negative look before assertions
            if ( !aNegLookBefore.some(sRegEx  =>  (RegExp.leftContext.search(sRegEx) >= 0)) ) {
                break;
            }
        } else {
            break;
        }
    }
    if (m === null) {
        return null;
    }

    let codePos;
    let iPos = 0;
    m.start = [m.index];
    m.end = [this.lastIndex];
    if (m.length > 1) {
        // there is subgroup(s)
        if (aGroupsPos !== null) {
            // aGroupsPos is defined
            for (let i = 1; i <= m.length-1; i++) {
                codePos = aGroupsPos[i-1];
                if (typeof codePos === "number") {
                    // position as a number
                    m.start.push(m.index + codePos);
                    m.end.push(m.index + codePos + m[i].length);
                } else if (codePos === "$") {
                    // at the end of the pattern
                    m.start.push(this.lastIndex - m[i].length);
                    m.end.push(this.lastIndex);
                } else if (codePos === "w") {
                    // word in the middle of the pattern
                    iPos = m[0].search("[ ~’,()«»“”]"+m[i]+"[ ,’~()«»“”]") + 1 + m.index
                    m.start.push(iPos);
                    m.end.push(iPos + m[i].length)
                } else if (codePos === "*") {
                    // anywhere
                    iPos = m[0].indexOf(m[i]) + m.index;
                    m.start.push(iPos);
                    m.end.push(iPos + m[i].length)
                } else if (codePos === "**") {
                    // anywhere after previous group
                    iPos = m[0].indexOf(m[i], m.end[i-1]-m.index) + m.index;
                    m.start.push(iPos);
                    m.end.push(iPos + m[i].length)
                } else if (codePos.startsWith(">")) {
                    // >x:_
                    // todo: look in substring x
                    iPos = m[0].indexOf(m[i]) + m.index;
                    m.start.push(iPos);
                    m.end.push(iPos + m[i].length);
                } else {
                    console.error("# Error: unknown positioning code in regex [" + this.source + "], for group[" + i.toString() +"], code: [" + codePos + "]");
                }
            }
        } else {
            // no aGroupsPos
            for (let subm of m.slice(1)) {
                iPos = m[0].indexOf(subm) + m.index;
                m.start.push(iPos);
                m.end.push(iPos + subm.length);
            }
        }
    }
    return m;
}