Function match

src/commonmark.js:1167–1175

(re)

// If re matches at current position in the subject, advance
// position in subject and return the match; otherwise return null.
var match = function(re) {
    var m = re.exec(this.subject.slice(this.pos));
    if (m === null) {
        return null;
    } else {
        this.pos += m.index + m[0].length;
        return m[0];
    }
};

// Returns the code for the character at the current subject position, or -1
// there are no more characters.