+1
While it might work for teaching, it's not reasonable to ask software
developers who want to write useful software to depend on haskell98
instead of base if they want more relevant types.
I'd go one step further and say that we're not just talking about
whether someone is an "advanced" user ei
It's harmless. But it's there to tell us that a RULE is not going to match
because the LHS involves a coercion that is not Refl or a variable. Matching
on more complex coercions is likely to be fragile, since they can take a
variety of forms.
So don't worry too much, but I'd be interested in
It is not only a matter of teaching, I think. After first learning the very
basics of a language, browsing the libraries that come included is a more or
less standard way of getting more acquainted with it. By including only the
abstract versions we are making it much harder to learn the common
