Monomorphism restriction - is this still needed for efficiency?

[Brian Hulley]

Hi -
I'm wondering if the monomorphism restriction is now just an anachronism 
from Haskell 98 or if it is still needed for efficiency ie should I just now 
use -fno-monomorphism-restriction when compiling all my code to consign it 
to the dustbin of history? :-)

A related question is, if it can still improve efficiency when applied to 
local bindings, whether it would be worthwhile to have an additional option 
to switch monomorphism off for top level bindings but still keep it for 
local bindings, since I can't think of any situation where I don't want a 
top level binding to be fully polymorphic.

Does anyone know of any situation where a top level binding should not be 
fully polymorphic?

Thanks, Brian.

-- 
Logic empowers us and Love gives us purpose.
Yet still phantoms restless for eras long past,
congealed in the present in unthought forms,
strive mightily unseen to destroy us.

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