haskell - Using when/unless without saving the result of a Monadic action -

is there way write without variable x?

foo =   x <- checker bar   when x dostuff

i'm imagining similar lambdacase:

foo' =   checker bar >>= \case     true -> dostuff     _    -> return ()

but without second case pattern, obviously.

the straightforward answer desugar do hand, , see if can write code that's equivalent prettier. do desugars to:

checker bar >>= \x -> when x dostuff

so, answer have checker bar >>= f, f equivalent

\x -> when x dostuff

well, that's lot partially applying when, right? except want supply second argument instead of first, need flip it:

checker bar >>= flip when dostuff

JVParth