Proposal: Add bool to Data.Bool

Henning Thielemann lemming at
Wed Sep 11 08:34:55 CEST 2013

On Tue, 10 Sep 2013, Oliver Charles wrote:

> Hello,
> I would like to propose that the following is added to Data.Bool in base:
> bool :: a -> a -> Bool -> a
> bool f _ False = f
> bool _ t True  = t
> (Aka, bool f t b = if b then t else f)

There is already the ifThenElse function (and I have if' in utility-ht). 
Their argument order is optimal for writing kinds of 'case':

But 'bool' would be consistent with 'maybe' and 'either' and should be in 
Data.Bool, not Prelude.

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