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1 point by akkartik 5082 days ago | link | parent

(Which is reason against PLT's use of [], but doesn't affect arc's chosen use.)

Incidentally [] has one major advantage over (): it doesn't require pressing the shift key every single time. In my vim and emacs I've swapped the two sets of keys in lisp mode.



2 points by rocketnia 5082 days ago | link

Which is reason against PLT's use of [], but doesn't affect arc's chosen use.

Hmm? I don't provide any reasons against Racket's claim that "Using square brackets in a few key places makes Racket code even more readable." In fact, I think it does aid a bit in readability, but it doesn't help when my goal is to correct sloppy brackets. XD

What I am saying is that Arc's [+ 1 _] syntax is about as convenient as (f- + 1 _) or (f-:+ 1 _). Arc also shares the ))]))) issue, a little. It would be more noticeable if more operators accepted functions as their last argument rather than their first argument.

Incidentally [] has one major advantage over (): it doesn't require pressing the shift key every single time. In my vim and emacs I've swapped the two sets of keys in lisp mode.

You mentioned this a while ago, so I've been using only [] in my languages-in-progress. ^_^ It also helps that I begrudge () and {} for looking too similar to each other. :-p The one thing I'm worried about is that ] and [ might be less distinguishable from each other than ) and ( are.

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1 point by akkartik 5082 days ago | link

It would be more noticeable if more operators accepted functions as their last argument rather than their first argument.

Yeah, but they don't. Lisp idiom tends to be to put the values being operated upon last, and with good reason: you want to put last the arg most likely to be a temporary. Otherwise you risk separating function calls from their args. Compare:

  (some-function
     (some-verbose-computation
       ...
       ...)
     arg2 arg3)
with:

  (some-function arg2 arg3
    (some-verbose-computation
      ...))
Since there's this major structural constraint I think any dispatch in lisp should be on the type of the last arg. (http://arclanguage.org/item?id=12646)

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