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

Malcolm Wallace malcolm.wallace at
Sun May 26 11:21:25 CEST 2013

On 21 May 2013, at 06:06, Carter Schonwald wrote:

> lets see what concerns there are
> 1) will any code break? Nope!
> 2) does the change make learning the language more challenging? No.

One concern that is conspicuously missing from your list is

3) performance.  Will my code get slower, because it now has many more class dictionaries, requiring new runtime indirections?

I quote from the GHC manual:

"Overloaded functions are not your friend:
Haskell's overloading (using type classes) is elegant, neat, etc., etc., but it is death to performance if left to linger in an inner loop."


More information about the Libraries mailing list