Function returns value without replacing the variable with the given parameter

Question

sry about the stupid way I phrased the question here's some explanation: I am experimenting with lambda-calculus in javascript and I am having some minor difficulties. (you don't have to know anything about lambda-calculus to help me)

I have this function (the church numeral 1 btw):

function num1(c) {
return function(x){
    return c(x);
}
 }

alert(num1)

Behaves as expected and gives the exact same thing as above.

alert(num1(num1))

Behaves unexpected and gives:

function (x) {
    return c(x);
}

Why doesn't the javascript replace the 'c' with the function num1? but

alert(num1(num1)(num1))

Gives:

function (x) {
    return c(x);
}

And shows that the first c was in fact replaced by the function as it was supposed to. If the 'c' would not have been replaced, then this would have happened:

(num1(num1)(num1))=

(function (x) {return c(x);}(num1=

c(function num1(c) {
    return function(x){
        return c(x);
    }
})

So all in all, the code is doing what is it supposed to, but it doesn't output the function with the 'c' replaced. What can I do? Later, I will more functions and then I wont be I able to tell num1(asd) and num1(jkl) apart because the 'c' doesn't get replaced.

Thank you very much for your help!

Someonelse

Answer 1

Why don't you try this:

function num1(c) {
   function rv(x){
    return c(x);
  }
   rv.showBinding = function() {
     return c;
   }

   return rv;

}

Then:

alert(num1);
alert(num1(num1).showBinding());