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0 pointstom_mellior9y ago0 comments

> It's silly, but it's really hard to evaluate a language if you can't read the examples.

No, this is not a silly notion. But I don't think the difference Reason makes is as big as you think. I mean, I don't really believe that you can read this:

  let foo = if (cond) { x } else { y };
  foo + 1

but not this:

  let foo = if cond then x else y
  in
  foo + 1

0 comments

ngrilly9y ago

The 'in' is what makes it difficult to understand for someone not familiar with OCaml syntax and semantics. Reason makes it easier.

tom_melliorOP9y ago

I've heard that said, but I don't see how it's a big deal. OK, the very first example introducing let bindings would have to come with a sentence like "the 'in' part of 'let ... in' means 'in' just like in English: 'let' the binding be valid 'in' what follows". You don't have to define a whole new syntax where a single sentence in a language tutorial might be enough.

But I admit that I probably can't fully appreciate whether this is really difficult for someone used to JavaScript.

jordwalke9y ago

Except when you're in the top level - in which case you don't use `in`. Oh, and don't forget all the nuance of interleaving imperative commands. I'm an experienced OCaml dev and this trips me up (the "ml compared" section of the docs lists some common pitfalls that Reason resolves).

1 more reply

ngrilly9y ago

Of course, once you know what 'in' means, it's easy to read, but you have to learn it, and get used to it. I've teached programming to students in finance, and this learnt me how much I underestimated the impact small things like that can have on the learning curve (and the motivation).

ubertaco9y ago

Yeah, I don't know what doesn't read easily about "let x = 3 in x - 1" -- it is straightforward: x is equal to 3 in the expression "x - 1".

eru9y ago

Hmm, the new if syntax really feels like a step backwards. (But I can see why they chose it: the C-like syntax here isn't too much of a burden, and is familiar to a lot of programmers already.)

j / k navigate · click thread line to collapse

0 pointstom_mellior9y ago0 comments

> It's silly, but it's really hard to evaluate a language if you can't read the examples.

No, this is not a silly notion. But I don't think the difference Reason makes is as big as you think. I mean, I don't really believe that you can read this:

  let foo = if (cond) { x } else { y };
  foo + 1

but not this:

  let foo = if cond then x else y
  in
  foo + 1

0 comments

ngrilly9y ago

The 'in' is what makes it difficult to understand for someone not familiar with OCaml syntax and semantics. Reason makes it easier.

tom_melliorOP9y ago

But I admit that I probably can't fully appreciate whether this is really difficult for someone used to JavaScript.

jordwalke9y ago

1 more reply

ngrilly9y ago

ubertaco9y ago

Yeah, I don't know what doesn't read easily about "let x = 3 in x - 1" -- it is straightforward: x is equal to 3 in the expression "x - 1".

eru9y ago

Hmm, the new if syntax really feels like a step backwards. (But I can see why they chose it: the C-like syntax here isn't too much of a burden, and is familiar to a lot of programmers already.)

j / k navigate · click thread line to collapse