I’m trying to use Data.Map, mapWithKey. The compiler says it’s not exported by Data.Map. I checked every version in the documentation and I think all versions of Data.Map have mapWithKey. I’m not sure which version I’m using.
Wait… I get it. Map is a functor. So it’s just ‘map’ to do the equivalent of Haskell’s Map.map. But what is mapWithKey?
PureScript has the
FoldableWithIndex classes. So
Your confusion might be due to the fact that the
Map type was previously part of the package
purescript-maps, but now lives in
purescript-ordered-containers. Incidentally, if you’re using Bower, you can check which version of a given package you’re using by having a peek at
mapWithKey was removed after being made redundant by the