Function.prototype._jbNamedApply.js

/**
  @fn call function with <this> = <that> and <arguments> matched from <argMap> by names
  @param that {Any} <this> for function call
  @param argMap {Object} map argName -> argValue
  @example
    var _fn = function(a, b, c)
    {
      console.log('a = ', a, 'b = ', b, 'с = ', c); 
    };

    _fn._jbNamedApply(null, {b: 1}); // a =  undefined b =  1 с =  undefined
    _fn._jbNamedApply(null, {b: 1, a: 0}); // a =  0 b =  1 с =  undefined
    _fn._jbNamedApply.call(1, 1, {}); // TypeError: first argument must be function
    _fn._jbNamedApply(null, 1); // TypeError: 3rd argument must not null
    _fn._jbNamedApply(null, {b: 1, a: 0, d: 3}); // SyntaxError: function hasnt argument "d"
  
    var _fn2 = function(){};
    _fn2._jbNamedApply(null, {b: 1, a: 0, d: 3}); // SyntaxError: function hasnt named arguments
  @return result of function call
*/
Function.prototype._jbNamedApply = function(that, argMap)
{
  var _fn = this;
  
  if(typeof(_fn) != 'function')
    throw new TypeError('first argument must be function');

  if(argMap == null)
    throw new TypeError('3rd argument must not null');
    
  var argToPosMap = _fn.jbArgToPosMap_;
  
  if(argToPosMap == null)
  {
    var fnCode = '' + _fn;
    
    var argString = fnCode.slice(fnCode.indexOf('(') + 1, fnCode.lastIndexOf(')', fnCode.indexOf('{'))). // get arguments string
      replace(/\/\*[\s\S]*?\*\//g, ''). // and strip comments
      replace(/\/\/[\s\S]*?\n/g, '').
      /*#if $jb.Deploy._const('support:String.prototype.trim') */
      /*## trim() */
      /*#else*/
      replace(/^\s+|\s+$/g, '')
      /*#endif*/
      ;
      
    argToPosMap = _fn.jbArgToPosMap_ = {};

    if(argString)
    {
      var argNames = argString.split(/\s*,\s*/);
      
      var i = -1, len = argNames.length; while(++i < len)
        argToPosMap[argNames[i]] = i;
    }
    else
    {
      _fn.jbHasntArguments_ = true;
    }
  }
  
  if(_fn.jbHasntArguments_)
  {
    /*#if $jb.Deploy._const('support:Object.prototype.__count__') */
    /*## if(argMap.__count__) throw new SyntaxError('function hasnt named arguments'); */
    /*#else*/
    for(var name in argMap)
    {
      if(argMap.hasOwnProperty(name))
        throw new SyntaxError('function hasnt named arguments')
    }
    /*#endif*/
  }
  else
  {
    var argValues = [];
    
    for(var name in argMap)
    {
      if(argMap.hasOwnProperty(name))
      {  
        var pos = argToPosMap[name];

        if(pos == null)
          throw new SyntaxError('function hasnt argument "' + name + '"')
        
        argValues[pos] = argMap[name];
      }
    }
    
    return _fn.apply(that, argValues);
  }
};