Re: foldable flexible bridges (putting foldable+traversable in prelude) Re: Burning bridges

One potentially palatable option would be to just note that incorporating these into the a Prelude can be done while leaving the haskell98 and haskell2010 packages with the current behavior. Really, it would have to. This means that in the bizarre circumstance that someone relies on the exact current behavior for teaching purposes, there is a path forward for them. -Edward On May 21, 2013, at 11:02 AM, Casey McCann wrote:

On Tue, May 21, 2013 at 6:22 AM, Henning Thielemann wrote:

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On Tue, 21 May 2013, Carter Schonwald wrote:

...

2) does the change make learning the language more challenging? No. In fact, i've encountered *many* more smart people getting confused as to why the map / fold etc in prelude are all list specific than i've seen people struggle with type classes.

The Haskell beginners I know, even have problems with 'map' and even more 'fold' being higher order functions.

Notwithstanding that anyone having trouble with a monomorphic foldr is unlikely to be significantly worse off with the Data.Foldable version, and notwithstanding also that I've seen redundant monomorphic functions create more confusion than they seem to avoid, the base objection here is and always has been misguided at best.

Being a beginner is by definition an ephemeral state; the entire purpose of being a beginner is to eventually stop being one. Don't design a language (or anything else) around the needs of beginners unless you intend that only beginners will use it, in which case one wonders why they're even bothering.

- C.

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