default instance for IsString

Yitzchak Gale gale at
Wed Apr 25 13:00:57 CEST 2012

Erik Hesselink wrote:
> I don't think IsString should be dismissed so easily.

I'm just saying I don't want to be forced to use it.
If others like it, I'm not dismissing it.

> we have a couple of newtypes over Text that do different kinds of
> normalization. An IsString instance for these is useful and total.

True. Perhaps you'd be able to get IsBuiltinString instances
for those too, using newtype deriving, if only the method
names of IsBuiltinString are hidden and the class name is

If that doesn't work, I'm fine with using a quasiquoter for
those instead. Or even just the usual newtype unwrapping
and wrapping. And again, if you provide IsString and others
want to use it, that's fine.


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