Convert dumb quotes to smart quotes and add em dashes where needed.

Smartify.js

String.prototype.Smartify = function () {
    var base = this.valueOf(); // gets the value of the original string
    var _a = new RegExp(/([\"]([a-zA-Z0-9\s\S]{0,}?)([\"]))/, 'gm'); // filter for large chunks of dumb quotes ["which is shit like this"]
    var _b = new RegExp(/([^\"]([a-zA-Z0-9\s\S]{0,}?)([^\"]))/, 'gm'); // sub-filter for everything that isn't dumb quotes [which is shit like this]
    var _c = new RegExp(/([0-9]){1,}([\"]){1}/, 'gm'); // filter for smartifying [5"] with [5“]
    var _d = new RegExp(/([^\s0-9]{1,}[\'][a-zA-Z]{1,})/, 'gm'); // filter for getting words like [don't] and [couldn't]
    var _e = new RegExp(/([\']([a-zA-Z0-9\s\S]{0,}?)([\']))/, 'gm'); // gets large chunks of dumb apostrophes like ['What did she say?'] and ['thus we heard it']
    var _f = new RegExp(/([^\s0-9]{0,}[\'][a-zA-Z]{0,})/, 'gm'); // gets the remaining dumb apostrophes like ['bout] and [lyin']
    var _g = new RegExp(/(\s[\-]{1,2}\s)|((\s){0,1}[\-]{2}(\s){0,1})|((\s){0,1}[\-]\s)|(\s[\-](\s){0,1})/, 'gm'); // gets all the makeshift em dashes and converts them to REAL em dashes
    var _h = new RegExp(/[\"]/, 'gm'); // matches all dumb quotes
    var _i = new RegExp(/[\']/, 'gm'); // matches all dumb apostrophes
    var _j = new RegExp(/[\-]/, 'gm'); // gets all simple dashes

    var mod_string = 
        base.replace(_c, function (a) {
            var b = a.replace(_h, "");
            return `${b}“`;  // converts shorthand inches measurement [6"] to use a smart quote
        }) .replace(_a, function (a) {
            var b = a.replace(_h, "");
            return `“${b}”`; // converts quotations to use smart quotes
        }) .replace(_d, function (a) {
            var b = a.replace(_i, "’");
            return b; // converts words like [don't] to use a smart quote
        }) .replace(_f, function (a) {
            var b = a.replace(_i, "’");
            return `${b}`;
        }) .replace(_e, function (a) {
            var b = a.replace(_i, "");
            return `‘${b}’`; // converts apostrophes to use
        }) .replace(_g, " — ") // em dash conversion
           .replace(_j, "–"); // replaces simple dashes with long conjunctive dashes
    
    return mod_string;
};

Sample paragraph:

At one o'clock, we were all at work again. I, having completed sixty-four lids, and the supply being consumed, was put at "molding in." Everybody was rushing- girls of all ages and appearances and hurrying men- and I went along, as one of the throng. It was the boys' tower. Famed to be said to be "ain't worth nothing." I was shocked, a man of about 6'5" has just given me the "ok" to say 'no.' It couldn't have been this way. Shocked-- as he was. No--he mustn't, it was only feasible to continue towin' on.