Parse javascript function from json string

parse.js

if (typeof String.prototype.parseFunction != 'function') {
    String.prototype.parseFunction = function () {
        var funcReg = /function *\(([^()]*)\)[ \n\t]*{(.*)}/gmi;
        var match = funcReg.exec(this.replace(/\n/g, ' '));

        if(match) {
            return new Function(match[1].split(','), match[2]);
        }

        return null;
    };
}


function parseToFunction(t, func) {
  switch (t?.constructor) {
    case Object:
      return Object.fromEntries(
        Object.entries(t).map(([k,v]) =>
          [k, func([k, parseToFunction(v, func)])]
        )
      )
    case Array:
      return t.map((v, k) => func([k, parseToFunction(v, func)]))
    default:
      return func([null, t])
  }
}

var data = {
    "processing": true,
    "serverSide": true,
    "serverMethod": "post",
    "ajax": {
        "url": "data",
        "cache": false,
        "callback": "function(arg){console.log(arg)}"
    },
    "others": [
        {"anoher_callback": "function(arg){console.log(arg)}"},
        {"something": "function(arg){console.log(arg)}"}
    ]
};

console.log(parseToFunction(data, ([k,v]) =>
  (typeof v === 'string' && v.slice(0, 8) == "function") ? v.parseFunction() : v
))

stringify.js

var myobj = {
    "sayhello": function (name) {
        console.log(name);
    }
};

var functions = [];

var result = JSON.stringify(myobj, function (key, val) {
    if (typeof val === 'function') {
        functions.push(val.toString());
        
        return "{func_" + (functions.length - 1) + "}";
    }
        
    return val;
}).replace(/"\{func_(\d+)\}"/g, function (match, id) {
    return '"'+functions[id]+'"';
});

console.log(result);