Re: poll: polymorphic let bindings in do

[Marcin 'Qrczak' Kowalczyk]

Sun, 4 Jun 2000 14:57:05 -0700, Levent Erkok <[EMAIL PROTECTED]> pisze:

> > And "<-"-bound variables would be visible everywhere too?
> 
> That's right.

I think "let" in the syntax can be dropped.

One reason of having "let" is that we must distinguish between
    do
        let x = e1
        let y = e2
        ...
and
    do
        let x = e1
            y = e2
        ...
where e1 can refer to y in the second case but not in the first.

Unfortunately the layout rules make it inconvenient:
    do
        x <- long expression
            split into lines and indented - this is OK.
        let y = another long expression
                must be indented more!
        ...

It would be nice to be able to write just
    do
        x = e1
        y = e2
        ...
probably even keeping the old let for compatibility.

-- 
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