[Haskell-cafe] Instance match surprise

Imants Cekusins imantc at gmail.com
Mon Feb 1 20:39:04 UTC 2016

.. could we say:

main purpose of instance contexts is to allow use of 'open' (e.g. a)
types when defining instance methods (i.e. we can use
(==) a
inside instance method if the context says Eq a)

, rather than for looking up an applicable instance?

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