Optics.Operators.Unsafe

Documentation

(^?!) :: (HasCallStack, Is k An_AffineFold) => s -> Optic' k is s a -> a infixl 8

Perform an *UNSAFE* head of an affine fold assuming that it is there.

>>> Left 4 ^?! _Left
4

>>> "world" ^?! ix 3
'l'

>>> [] ^?! _head
*** Exception: (^?!): empty affine fold
...

Since: 0.3