[REBOL] Re: func args by ladislav
From: lmecir:mbox:vol:cz at: 16-Oct-2001 16:35
Hi Romano,
I don't think, I must change your mind, but there is a difference you
probably don't see. It is possible to define a Rebol function (a FUNCTION!
datatype value to be exact), that takes one argument and evaluates it:
do-f-0: func [f] [
f
]
1) DO-F-0 is able to evaluate any zero-argument function supplied as the F
argument.
2) DO-F-0 is unable to evaluate any one-or-more-argument function supplied
as the F argument
Similarly it is possible to define a function that takes two arguments and
evaluates the first one supplying it the second one as its argument:
do-f-1: func [f arg1] [
f :arg1
]
do-f-2: func [f arg1 arg2] [
f :arg1 :arg2
]
etc.
3) I think, that we are in agreement, how many arguments the above defined
functions take. It is evident, that for a Rebol function to evaluate its F
argument, the function must take n + 1 arguments, where n is the number of
arguments of F.
4) Can you write a Rebol function (a FUNCTION! datatype value) able to
evaluate any F (i.e. F with any number of arguments) without cheating, i.e.
without "packing" the arguments into a block?
Cheers
Ladislav
