Pass function with parameters, but not its execution result

Question

In my component I have a static need property that stores a function . Behind the scenes there is middleware that executes this function in order to perform some asynchronous API calls before rendering the component. This is how it looks:

static need = [
  myFunc(token)
]

However this causes issues, as having a token parameter there actually executes the function, hence its promise is passed as need , instead of function itself. For example, this works perfectly fine, as it doesn't execute the function:

static need = [
  myFunc
]

But this way I have no ability to pass a token. I'm trying to figure out how to pass this function to need with a token, but without executing it, as it is done in middleware.

Answer 1

you can do

var need = [
  myFunc, token
];

you can invoke it as

need[0].apply(null, need.slice(1-need.length));

Example DEMO

 function a(b){ console.log(b) } var need = [ a, "1" ]; need[0].apply(null, need.slice(1-need.length)); 

Answer 2

Given that you have control of myFunc :

function myFunc(params) {
   return function() {
      // do something with params
   }
}

So in order to execute actual function code, you'll have to call it twice: myFunc('foo')() , which suits your need to maintain parameters before calling a function.

Answer 3

You could use a closure

static need = [
    function (token) {
        return myFunc;
    }(token);
]

ES6

static need = [
    (token => myFunc)(token)
]

Answer 4

Probably by now you have resolve the issue but I feel instead of storing it in an array you can create an object & add this as an object property.There is no harm in storing it in an array

//Define the function
var need = {
  myFunc:function(token){
   alert(token)
  }
};

// Invoking
need['myFunc'](1);

//dynamic invoke
var dynamicInvoke = 'myFunc';
need[dynamicInvoke](2);

JSFIDDLE