Re: [Haskell-cafe] Execution Contexts

Ben, On Sat, 27 Nov 2004, Benjamin Franksen wrote (apropos ACIO topdecls):

... a highly controversial new language feature.

The language feature is easily done, and just what has been happening all along: type ACIO = IO declare :: ACIO a -> a {-# NOINLINE declare #-} declare e = unsafePerformIO e All 'affine central' does is give a label to one particular idiomatic use of IO. The controversial part would be wading through libraries arguing over what things were ACIO. OK, I admit it would be nice if the compiler would manage everything, use <- syntax, and take advantage of affine central actions being well-behaved. But not vital. Ian