Type families and type inference - a question

Yitzchak Gale gale at sefer.org
Sun Jan 10 14:40:34 EST 2010

Daniel Fischer wrote:
> (Note: Surprisingly (?), if you load a module with
> {-# LANGUAGE NoMonomorphismRestriction #-}
> , the monomorphsm restriction is still enabled at the ghci prompt, so we
> have to disable it for that again - or we could have loaded the module with
> $ ghci -XNoMonomorphismRestriction Movie)

IMHO, the monomorphism restriction does not make sense at the
GHCi prompt in any case, no matter what you have or haven't
loaded, and no matter what your opinion of MR in general.

I recommend that you create a file called ".ghci"
in your home directory, and put into it the line:

:set -XNoMonomorphismRestriction

Then you won't be bothered by this anymore for things
that you type in at the prompt.

I think this may be scheduled to be fixed in a coming version
of GHCi.


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