I am looking to be able to create two functions, BaseFunction and CallbackFunction where BaseFunction takes in a variable set of parameters as such:

BaseFunction(arg1, arg2, ....)
{
    //Call the Callback function here
}

and callback function receives the same parameters back:

CallbackFunction(value, arg1, arg2, ...)
{

}

How can I pass the parameters from the base function to the callback function?

I am looking to be able to create two functions, BaseFunction and CallbackFunction where BaseFunction takes in a variable set of parameters as such:

BaseFunction(arg1, arg2, ....)
{
    //Call the Callback function here
}

and callback function receives the same parameters back:

CallbackFunction(value, arg1, arg2, ...)
{

}

How can I pass the parameters from the base function to the callback function?

• javascript
• parameters
• parameter-passing
• optional-parameters

3 Answers 3

Use apply to call a function with an array of parameters.

BaseFunction(arg1, arg2, ....)
{
    // converts arguments to real array
    var args = Array.prototype.slice.call(arguments);
    var value = 2;  // the "value" param of callback
    args.unshift(value); // add value to the array with the others
    CallbackFunction.apply(null, args); // call the function
}

DEMO: http://jsfiddle/pYUfG/

For more info on the arguments value, look at mozilla's docs.

to pass arbitrary number of arguments:

function BaseFunction() {
     CallbackFunction.apply( {}, Array.prototype.slice.call( arguments ) );
}

This kind of does the trick:

BaseFunction(arg1, arg2, ....)
{
  CallbackFunction(value, arguments);
}

However CallbackFunction needs to accept array:

CallbackFunction(value, argsArray)
{
  //...
}