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Comment by braythwayt | Hacker News Reader

Looks interesting, especially in concert with the proposed bind syntax. Fortunately, that syntax is in Babel now, so we can play with these ideas straight away.

That being said, the readme did not address why Ramda uses the data as the last parameter and not as `this`: To facilitate partial application.

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Ramda actually uses data as the last parameter usually, whereas lodash has it as the first.

However, I agree, the readme doesn't quite show the full power of Trine. Trine has `partial`, which allows you to do partial application as so: `parseInt::partial(_)`, that would create a function that acts as parseInt but only takes one argument. This is in sync with the partial application syntax proposal: https://gist.github.com/anonymous/5c4f6ea07ad3017d61be

The rest of the functional goodness, such as autocurrying are still undecided upon because in my personal experience autocurrying in JS is awkward and leads to bugs that are hard to debug. I'm also considering compose and a combination of compose and partial (e.g. apply a function to a parameter at a certain place), but again subjectively, composing functions like that has reduced the readability of codebases. JS already has first class functions which allows composition pretty easily, the only problem is that it's overtly verbose - I'm still hoping to see the single arrow function land in JS some day. :)

May I ask what do you mean by "single arrow function"?

Do you mean thin arrow fn(s)?

Yes, sorry, thin arrow, not single - `() -> this.foo()` for function expressions and possibly even `let/const fn () -> this.foo()` for declarations.

Excuse my ignorance but I only have experience in JS and not any other "advanced" or well-established programming langs, how's thin arrow syntax gonna fix this prob that fat arrow can't?

Fat arrow functions have lexical this: this inside the function is bound to what it was outside. Thin arrow functions have a dynamic this, determined by how they are called. Because the library relies on dynamic this as the place where the data is sent, fat arrow syntax isn't useful with it.

Thanks for the explanation.

Whoops, my mistake, I meant to say last parameter, which is exactly its point. I recall discussing this with the authors at length, because allong.es usues a similar strategy with functions named ___With, e.g. mapWith, filterWith.

lodash-fp is a thin layer over lodash enabling auto-curried, data last methods – https://www.npmjs.com/package/lodash-fp

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