Proposal: adding 'tailDropWhile' to Data.List

Kazu Yamamoto ( 山本和彦 ) kazu at iij.ad.jp
Fri Sep 30 04:35:37 CEST 2011


Hello,

> Hmm. I wrote this attempting to satisfy the goals of "lazy and
> efficient", but on second thoughts it seems like Aoe's original
> function was both. You seem to be under the impression that it's more
> strict, but I think it's just as lazy as the others. Can you provide
> evidence of its strictness?

In my definition, if
  tailDropWhile isSpace $ " foo bar  " ++ undefined
returns " foo bar" and then an error, it's lazy.
If it causes an error without " foo bar", it's strict.

This is my fault. Aoe's one is also lazy.

--Kazu



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