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messe • today at 1:50 PM • 2 replies • view on HN

That's not what I'm talking about.

The article draws a three way distinction between curried style (à la Haskell), tuples and parameter list.

I'm talking about the distinction it claims exists between the latter two.

Replies

disconcision • today at 2:03 PM

all three are isomorphic. but in some languages if you define a function via something like `function myFun(x: Int, y: Bool) = ...` and also have some value `let a: (Int, Bool) = (1, true)` it doesn't mean you can call `myFun(a)`. because a parameter list is treated by the language as a different kind of construct than a tuple.

antonvs • today at 2:44 PM

A language which truly treats an argument list as a tuple can support this:

    args = (a, b, c)
    f args
…and that will have the effect of binding a, b, and c as arguments in the called function.

In fact many “scripting” languages, like Javascript and Python, support something close to this using their array type. If you squint, you can see them as languages whose functions take a single argument that is equivalent to an array. At an internal implementation level this equivalence can be messy, though.

Lower level languages like C and Rust tend not to support this.

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