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1 point by almkglor 6001 days ago | link | parent

> 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)))


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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