Question

I am working on a javascript framework. I have several independent scripts that look like this:

core.modules.example_module = function(sandbox){
    console.log('wot from constructor ==', wot);

  return{
    init : function(){
      console.log('wot from init ==', wot);
    }
  };
};

this function is called from another external script. I am trying to pass variables in to this function so that they can be accessed without using the this keyword.

The above example will error out saying wot is undefined.

If i wrap the function in an anonymous function and declare the variables there I get the expected desired results

(function(){

var wot = 'omg';

core.modules.example_module = function(sandbox){
    console.log('wot from creator ==', wot);

  return{
    init : function(){
      console.log('wot from init ==', wot);
    }
  };
};

})();

What i am trying to do is declare the variables further up the scope chain so they can be accessed in the module without using the this keyword like the second example. I don’t believe this is possible as it looks like the functions execution scope is sealed on declaration of the function.

update
To clarify where I am trying to define wot. In a separate javascript file I have an object that calls a register module function like this

core = function(){
   var module_data = Array();
   return{
    registerModule(){
      var wot = "this is the wot value";
      module_data['example_module'] = core.modules.example_module();
    }
  };
};

Answer 1

What you’re looking for is called “dynamic scoping“, where bindings are resolved by searching the current call-chain. It’s not too common outside of the Lisp family (Perl supports it, via the local keyword). Dynamic scoping is not supported in JS, which uses lexical scoping.