[Haskell] Read Instances for Data.Map and Data.Set

Malcolm Wallace Malcolm.Wallace at cs.york.ac.uk
Thu Oct 20 06:16:42 EDT 2005

Georg Martius <mai99dgf at studserv.uni-leipzig.de> writes:

> I was really annoyed by the fact that for Data.Map and Data.Set are no Read 
> instances declared, but Show instances are! I believe there should be some 
> kind of unwritten rule that in the standart lib the Show and Read instances 
> come pairwise and are fully compatible. 

FWIW, earlier versions of Haskell had a single class Text with
methods for both showing and reading, so it was harder to ignore
their complementary roles.


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