Re: [Chicken-users] Re: A few questions

[John Cowan]

Elf scripsit:

> >(define (foo . rest) (if (= 1 (random 1)) (car rest) #f)
> 
> in this case, 0.  this entire expression should have been removed by the
> compiler and replaced by #f, though.

Okay, make it (random 2) then, smartass.

> additionally, this is enough information, even unevaluated, to do
> many checks at compiletime and leave only the relevant unresolved bits
> (if any) runtime checked.

By all means.  But you keep saying "It's easy", when what you mean is
"Some subcases are easy."

> so the multiple-argument procedure form generalises to a nested
> single-argument procedure form.

I understand currying; it's the reciprocal claim about multiple values
I didn't and don't follow.

> if values was the first-class dual of an argument list, 

[example snipped]

> if it was a dual, that resolution and application should work, methinks.

That disposes of the claim that multiple values is the dual of an argument
list, but that's not my claim:  my claim is that multiple values is the
dual of multiple arguments, and neither one needs a list to implement
unless the number of arguments or values is indefinite.  You can pass
arguments in registers (broadly construed), and you can pass back values
in registers too.

> values isnt a first-class object, its just a hack.

Only in the sense that passing multiple arguments rather than allowing
just one (a list, not a curried function) is a hack.  If it's a hack,
it's pretty basic to Scheme and most other languages (excepting ML,
Haskell, and Q).

> its why the most common form of the consumer lambda-list in
> call-with-values is just a rest arg. :)

Really?  I'd expect that, since most multiple-value-returning procedures
return a definite number of values, that a proper argument list would
be the most common case.  It's certainly the case that CL provides the
most support for.

(The below was randomly chosen without reference to the message I write
or the one it's responding to.)

-- 
John Cowan  address@hidden  http://ccil.org/~cowan
If I have seen farther than others, it is because I am surrounded by dwarves.
        --Murray Gell-Mann