lens-4.3: Lenses, Folds and Traversals

Portabilityportable
Stabilityprovisional
MaintainerEdward Kmett <ekmett@gmail.com>
Safe HaskellSafe-Inferred

Control.Lens.Extras

Description

A few extra names that didn't make it into Control.Lens.

Synopsis

Documentation

is :: APrism s t a b -> s -> BoolSource

Check to see if this Prism matches.

>>> is _Left (Right 12)
False
>>> is hex "3f79"
True