IncorrectAnonymousArgument Error

Example

module Example where

add = (_ + _)

mapArray = map _ [1, 2, 3]

Cause

In an operator section, like (_ + 1), an anonymous argument can be used only once.

Fix

In the case of multiple arguments, give them names:

add a b = (a + b)

or in the case of a normal function: Write the function as an operator using backticks:

mapArray = _ `map` [1, 2, 3]

Notes

• While _ + _ will give this error; \a -> a + _ will not

• If you really want to have multiple anonymous arguments, it can be achieved like this:

add = (((+) $ _) $ _)