JavaScript Getter-Setter Pyramid

Re:JavaScript Getter-Setter Pyramid by SeanLuke on Wednesday December 19, 2018 @10:51AM (#18716439)

I'm interested in this simple closure code from the article:

     function getGetNext() {
       let i = 2;
       return function getNext() {
         const next = i;
         i = i * 2;
         return next;
        }
     }

As a lisp coder [and not a JS coder], I'm wondering: why does the function getNext() have to be named? Why not just say something like:

     function getGetNext() {
       let i = 2;
       return function() {
         const next = i;
         i = i * 2;
         return next;
        }
     }

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Re:JavaScript Getter-Setter Pyramid by kangoo1707 on Wednesday December 19, 2018 @10:54AM (#18716465)

It doesn't have to be named, your second example still works

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Re:JavaScript Getter-Setter Pyramid by wbrasky on Wednesday December 19, 2018 @11:03AM (#18716549)

naming anonymous functions can provide some clarity in stack traces however

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Re:JavaScript Getter-Setter Pyramid by SeanLuke on Wednesday December 19, 2018 @12:38PM (#18717506)

I got the syntax right? Was completely guessing.

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Re:JavaScript Getter-Setter Pyramid by basil-rash on Wednesday December 19, 2018 @02:55PM (#18718913)

Yep. Nowadays you'd be more likely to see it as:

    return () => {
      const next = i;
      i = i * 2;
      return next;
    }

But in this case the two are equivalent.

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Re:JavaScript Getter-Setter Pyramid by interesthrow2 on Wednesday December 19, 2018 @05:08PM (#18720234)

Or as an alternative one can use a generator, they are built for that purpose AND are supported by a wide range of other JS constructs without any need to create iterators manually and all that.

   function * getNext(){
       let i = 2;
           while(true){
               i = i * 2;
               yield i;
           }
   }

Here, no closure needed.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guid...

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Re:JavaScript Getter-Setter Pyramid by eithed on Thursday December 20, 2018 @05:19AM (#18723755)

I think that's no longer getter-getter and the example was to show a function that explicitly returns a function.

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Re:JavaScript Getter-Setter Pyramid by netghost on Wednesday December 19, 2018 @08:07PM (#18721649)

The name is optional, and probably just to help explain the code.

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