What are real use cases of currying?

Question

I've been reading lots of articles on currying, but almost all of them are misleading, explaining currying as a partial function application and all of examples usually are about functions with arity of 2, like add function or something.

Also many implementations of curry function in JavaScript makes it to accept more than 1 argument per partial application (see lodash), when Wikipedia article clearly tells that currying is about:

translating the evaluation of a function that takes multiple arguments (or a tuple of arguments) into evaluating a sequence of functions, each with a single argument (partial application)

So basically currying is a series of partial applications each with a single argument. And I really want to know real uses of that, in any language.

Answer 1

Real use case of currying is partial application.

Currying by itself is not terribly interesting. What's interesting is if your programming language supports currying by default, as is the case in F# or Haskell.

You can define higher order functions for currying and partial application in any language that supports first class functions, but it's a far cry from the flexibility you get when every function you get is curried, and thus partially applicable without you having to do anything.

So if you see people conflating currying and partial application, that's because of how closely those concepts are tied there - since currying is ubiquitous, you don't really need other forms of partial application than applying curried functions to consecutive arguments.