Documentation

A container for heterogenous items. This container lets items of different types be used in the same aggregating container, like ArrayedM, GridM, or LayeredM.

When using ItemM you'll likely need to:

• Use the ScopedTypeVariables language extension and explicitly specify a forall m in your function declaration (if a type-variable is being used)
• Explicitly specify the type of your list of ItemM in the call to the aggregating container and wrap the list in parentheses

For example:

{-# LANGUAGE ScopedTypeVariables #-}

import FULE

...

someFn :: forall m => m (ArrayedM m Widget)
someFn = return $
  arrayedHoriz noPadding
    ([item someWidget
    , item someContainer
    , item someOtherWidget
    ]::[ItemM m Widget])

Reference: Heterogenous Collections

Like ItemM but run in the Identity monad.

Create an ItemM with a heterogenous item.