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Comment by auggierose | Hacker News Reader

Yeah, point-free sounds cool, until you actually try it out. Even in their example they are not point-free:

    compose(foo, bar, baz)

Here compose is applied to three "points" (which happen to be functions).

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That example is as point free as it gets. Just because the syntax doesn’t look like Haskell doesn’t really change that.

You are applying functions to arguments, aren't you? So "point-free" means you cannot apply a function to arguments on the left hand side of a definition, but you are allowed to do so on the right hand side? If that's point-free, it is also point-less.

tacit means a definition doesn't name it's arguments, not that it isn't applied to arguments. the word tacit means implied, so arguments are implicity worked upon, instead of explicitly.

tacit doesn't mean functions are nullary.

Yes, but that is the same as not applying a function to arguments on the left hand side of an equation, but still doing so on the right hand side. The question is, what is the point of not doing that on the left hand side, if you then go and still do it on the right hand side? Let me say it again: It's pointless.

If you tried to understand as hard as you're trying to argue, you wouldn't be having this argument.

There is nothing to understand here. As I said, it's pointless.

From the Wikipedia article:

> Tacit programming is of theoretical interest, because the strict use of composition results in programs that are well adapted for equational reasoning.

Now this is bullshit. See my explanation, as equations are symmetric, and you can swap left and right hand side.

Maybe you should try to understand harder.

No, you’re just failing to understand what “equational reasoning” means.

It has little to do with the idea of LeftSide = RightSide. In fact you don’t even need an “equation” in that sense, or any equality sign, to do equational reasoning.

Equational reasoning is when a program is evaluated (ie.: like when you simplify or factorize an equation in maths) by using substitution (or rewriting) rules: https://en.wikipedia.org/wiki/Rewriting

This is becoming funny.

I recommend this book for you, you should read it. I have: https://www.cambridge.org/core/books/term-rewriting-and-all-...

Funny indeed, that’s the first reference on the wiki article. shrugs

So you've read it?

I wouldn't think so, because you don't seem to know the first thing about equational reasoning, namely that it is ALWAYS ABOUT EQUATIONS.

I use point-free languages, and it’s completely okay if you don’t enjoy them. It’s just that I love them, and they’re fun for me, so I don’t like when people are just saying that they’re like objectively bad. Try them out, see if you like them! I personally like a concatenative/stack-based flavor, but you might not! :)

Point-free means that you don't bind variables, so this particular example is indeed point-free.

IMO It is point free even if the syntax is not as nice as Haskell. Same as foo . bar . baz

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