Comment by shib71 | Hacker News Reader

Comment by shib71 | Hacker News Reader

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You need to explain more - for example what do you mean by a "partial"? A quick search for "partial functions" gave me several links to mathematics articles. When I followed the links to the composition modules I got more of the same impenetrable context-less style.

What I did get from the article is something that works a lot like promises:

- async functions return type of "eventual" data (in your case, a function you pass a callback to)

- various other functions that can operate on that eventual data type to return more eventual data

What does this style offer that standard promises doesn't?

> You need to explain more - for example what do you mean by a "partial"? A quick search for "partial functions" gave me several links to mathematics articles.

The magic phrase you were looking for is "partial application." (Partial functions are a different, even more esoteric thing.) Basically, partially applying a function means you create a new function that calls the original with some of the arguments already filled in. For example, you could write this:

  var getUserList = partiallyApply(jQuery.getJSON, 'http://example.com/user-list');

and getUserList would then be a function that takes a callback and calls

  jQuery.getJSON('http://example.com/user-list', yourCallback)

I believe that using basic functional programming tools is a much more powerful way than using promises. The main issue with promises is that the code you write will be less replaceable, and less compatible with other code.

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