Overlapping and incoherent instances

Stephen Paul Weber singpolyma at singpolyma.net
Wed Jul 30 01:56:08 UTC 2014

Somebody signing messages as Felipe Lessa wrote:
>OTOH, the pragma is mostly harmless for older GHC versions, while the
>keyword approach needs a preprocessor.

Only if *both* the old LANGUAGE pragma and the new pragma were employed, 
which will generate a deprecation warning for awhile and then eventually 
(likely) be rejected by newer GHCs, thus requiring a prepropcessor in either 

Stephen Paul Weber, @singpolyma
See <http://singpolyma.net> for how I prefer to be contacted
edition right joseph

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