forget
Vlad Dumitrescu
vlad_dumitrescu@REDACTED
Tue Jun 11 09:45:48 CEST 2002
----- Original Message -----
From: "C.Reinke" <C.Reinke@REDACTED>
Thanks for the extended answer!
> > Please correct me if I am just confused. Language extensions are grat
>:-)
>You mean: extensible languages are great!-)
I didn't mean to get into a philosophical dicussion about programming
languages. While I find the topic very interesting, this might not be the
right place... :-)
> > {ok, A} = foo(Q),
> > {B, C} = bar(A),
> > {value, [D]} = baz(B, C),
>This still has some regularity, which one could try to capture:
> uncurry(F,{X}) -> F(X).
> uncurry(F,{X,Y}) -> F(X,Y).
> uncurry(F,{X,Y,Z}) -> F(X,Y,Z).
That was just an example. My point is that this "haskellian" style of
programming effectively disables one of the most compelling features of
Erlang (in my opinion): matching. The ability to write things like
[{H1, _, H2}=H, <<F:binary/8, R:binary>>=B] = Mod:fun(X)
is very powerful.
>Of course, one might ask whether the code should be that irregular
>in the first place (but who am I to say?-), as that means there is
>no other way to read and understand the code than looking at all the
>details and carefully tracking the changes in usage from call to call.
I can't see a way to always produce regular looking calls... but probably I
am just biased! :-)
>It's not just the variable names, it's that each part of the code
>does its own thing, and has to be understood on its own and in all
>its connections to the usage context.
Doesn't one have to do that anyway? Just because one knows that a function
returns (say) a certain tuple, it doesn't means one has understood it...
>I guess I'd prefer something like "..,let <lhs>=<rhs>,.." to stand
>for an implicit "..,forget(<vars(lhs)>),<lhs>=<rhs>,.." instead of
>having an explicit forget bif or the current f() in the shell.
It should maybe be more like
local <vars> in <lhs>=<rhs>, <lhs>=rhs>... end
because one might have already bound variables in <lhs> that one wants to
keep bound.
regards,
Vlad
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