On Tue, Aug 25, 2009 at 1:11 PM, Yitzchak Gale
Johan Tibell wrote:
Are all these small little functions really worth it? They're trivially defined using the current API... let developers use composition to define the rest?
I completely agree with you. But in this case, even though these functions really are trivial, they come up *all* the time, and there is just something awkward about them.
We certainly won't add more than one of the two:
justIf x b = guard b >> return x check p x = guard (p x) >> return x
As you showed they are awkward to express in point-free style but as you demonstrated above they're trivially expressed using the monadic operators and guard. That several people want several different variation also suggests that the proposed version perhaps isn't useful enough to warrant inclusion in the library. Cheers, Johan