[Haskell-cafe] IO vs MonadIO

Ivan Lazar Miljenovic ivan.miljenovic at gmail.com
Wed Sep 12 11:55:50 CEST 2012

On 12 September 2012 18:24, Sergey Mironov <ierton at gmail.com> wrote:
> Hi. Just a brief question. System.IO functions are defined in IO monad
> and have signatures like Foo -> IO Bar.
> Would it be better to have all of them defined as (MonadIO m) => Foo
> -> m Bar? What are the problems that would arise?

That would require MonadIO being defined in base, and might make some
existing code fail due to lack of type signatures (though I suppose
you could specify a default).

Ivan Lazar Miljenovic
Ivan.Miljenovic at gmail.com

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