Add a oneOf function to improve the ergonomics of NonDet.
#201
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As per a discussion with @robrix at ICFP, we should expose this function to make the `NonDet` interface slightly less forbidding.
src/Control/Effect/NonDet.hs
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| -- pure (a, b, c) | ||
| -- @ | ||
| choose :: (Foldable t, Alternative m) => t a -> m a | ||
| choose = getAlt . foldMap (Alt . pure) |
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What do you think about doing foldMapA instead? I personally find it much more generally useful, and it still enjoys good type inference properties.
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No objections at all to exposing foldMapA as well as choose.
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At that point, given that choose = foldMapA pure, it seems like we don’t gain much from including both. Thoughts?
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I’m a big fan of providing a single verb for “choose an element of this structure”, for a few reasons: both because I find existing foldMapA pure or asum . fmap pure patterns unreadable, or at best non-obvious, and also because I think this operation is extremely common. (I’ve been practicing some simple logic programs recently, and I needed choose in all of them.)
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Ok, makes sense 👍
What do you think about renaming it to not conflict with #198’s smart constructor? Perhaps oneOf?
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oneOf is fine by me. choose was a little too close to choice from parsers. Will make the change!
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Regardless of whether we include |
patrickt
changed the title
choose function to improve the ergonomics of NonDet.oneOf function to improve the ergonomics of NonDet.
As per a discussion with @robrix at ICFP, we should expose this
function to make the
NonDetinterface slightly less forbidding.