Re: [q-lang-users] where

[Tim H. <q...@st...>]

"Rob Hubbard" <hub...@gm...> writes:

> If you wish to use "let" syntax, then the "let" clause could end in
> "in" rather than a semi-colon:

Absolutely! It's one of the few ML-isms I still bother remembering - I
always read `let' as `let blah... in' in scheme and haskell.

>     let N = #S - 1 in
>       strip C S = strip C $ sub S 0 (N-1) if (S!N = C);
> 
> that would prevent it looking like a separate definition.
> 
> Further definitions sharing the let clause could be separated by
> something like "and also" (as opposed to "and" or "and then"). I can't
> see a way to provide elegant, "Q-ish" nesting without a terminating
> delimiter for a let clause though. This:
> 
>     let T2 = 2*T in
>       let S = T2+1 in
>         f T = sin S
>       //"end let"
>     and also
>       let P = T2-1 in
>         g T = cos P;
>       //"end let"
>     //"end let"
> 
> would still be ambiguous: which "let" does the "and also" match? An
> "end let" would just produce blocks, which Albert has already
> indicated would not be in keeping with Q. It's a problem.

OK, I've only half been following this, but is there some potential for
using tuples/braces to delimit such a list of local-scope assignments? 
If need be, how about some kind of (= , , , ...)  form for constructing a
scope? 
It's a bit Scheme of me, but hey :)

~Tim
-- 
<http://spodzone.org.uk/>