[Haskell] Real life examples

Benjamin Franksen benjamin.franksen at bessy.de
Wed Nov 24 18:49:13 EST 2004

On Thursday 25 November 2004 00:38, Ben Rudiak-Gould wrote:
> John Meacham wrote:
>  >With my mdo proposal, and I think all proposals brought forth, the
>  >module system behaves identically to how it normally does for
>  >namespace control. [...] modules do not change code at all, they
>  >are pure syntantic sugar for deciding what names you can see.
> I'm not sure I understand your mdo proposal correctly then. A lot of
> this debate has been over what should happen when a module has a
> top-level action like
>     x <- putStrLn "hello"
> Everyone agrees that "hello" should be printed at most once, [...]

And I thought at least everyone agreed that things like that should not be 
allowed. Instead, only a "safe" subset of things that are currently in IO 
should be allowed to appear at the top-level, such as creation of mutable 
reference cells.


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