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1 point by shader 6001 days ago | link | parent

lol, I realize that you could try and apply those three at the same time, but the "compile time" modifier was supposed to be used by the programmer to tell arc that it was safe to do just such a thing. Other wise, it would be evaluated at run time. So while you could use those three at once, it would like you say have an undefined consequence.

Basically, I thought that it might be useful to have functions that didn't eval all their args. At that point, they're only a few steps away from macros, and I thought it would be cool if we could unify them.

>transforms to a function Just shows I didn't understand it right. :) That makes more sense, but I'm still not sure I understand it. Oh well.

Does your p-m:def support matching based on function sigs?



1 point by almkglor 6001 days ago | link

> Basically, I thought that it might be useful to have functions that didn't eval all their args.

  (def foo-internal (x y z)
    (do-something x y z))

  (mac foo (x y z)
    ; eval x, don't eval y, eval z
    `(foo ,x ',y ,z))
> Does your p-m:def support matching based on function sigs?

Yes, although I'm not sure I quite understand what you're asking.

For example factorial works out like this:

  (p-m:def factorial
    "a factorial function"
    (1)  1
    (N)  (* N (factorial:- N 1)))

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1 point by shader 6001 days ago | link

Actually, what I meant by match on function sigs was: while writing a higher order function that wants a function as an input, can you require that it be a function that's signature implies one var, two vars, a list etc?

As to the non-evaling functions, I suppose we could have a macro that defined a macro / function combination; the resulting macro would expand into a call to the function with ' before each item in the arg list.

Oh, and I think that `(foo ,x ... is supposed to be `(foo-internal ,x ... Otherwise you have an infinitely recursive macro. :)

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1 point by almkglor 6001 days ago | link

> can you require that it be a function that's signature implies one var, two vars, a list etc?

Nope ^^

> Oh, and I think that `(foo ,x ... is supposed to be `(foo-internal ,x ... Otherwise you have an infinitely recursive macro. :)

Yep ^^

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