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1 point by eds 6117 days ago | link | parent

I chose 'safeset only because that is what is used internally in 'def. But I see that you would need to watch 'set to be completely sure no redefinitions had occurred.

So if you put a hook in 'set, and watched for local variables (really function parameters, because 'let is implemented in terms of 'fn) overriding function names, that would probably be enough to know a function hadn't changed. And that would hopefully remove the need for CL style type declarations.

Maybe this should be added as an option to the poll?



1 point by almkglor 6117 days ago | link

In fact, yes you really have to watch for locals either way - it's entirely possible to do this (I have, since I wanted to package Arki in a module-like object):

  (let (localfn localfn2
        help* sig source-file*) nil
    ; protect 'def from bashing Anarki help docstrings
    (= help* (table) sig (table) source-file* (table))
    (def localfn ()
      (prn "localfn!"))
    (def localfn2 ()
      (prn "!2nflacol"))
    (def globalfn ()
      (localfn) (localfn2)
      (prn "haha only global!")))

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1 point by eds 6117 days ago | link

Is that multi-variable form of 'let an Anarki thing? I don't remember seeing it before. It does look really cool though.

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1 point by almkglor 6116 days ago | link

It's part of the Arc core destructuring thing. For example:

  (let (x y z) (list 1)
    (prn x)
    (prn y)
    (prn z))
...will assign 1 to x, and nils to y and z. Basically it seems that destructuring is done in the following manner:

  (let gs4932 (list 1)
    (let x (car gs4932)
      (let y (car:cdr gs4932)
        (let z (car:cdr:cdr gs4932)
          (body ...)))))
(NOTE: not exact code, but basically this is how ac.scm handles destructuring)

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