Witchcraft.Monoid (Witchcraft v1.0.4) View Source

Monoid extends the semigroup with the concept of an "empty" or "zero" element.

Type Class

Semigroup  [append/2]
    ↓
 Monoid    [empty/1]

t()

empty(sample)

An "emptied out" or "starting position" of the passed data.

empty?(monoid)

Check if a value is the empty element of that type.

zero(sample)

t() :: any()

An "emptied out" or "starting position" of the passed data.

iex> empty(10)
0

iex> empty [1, 2, 3, 4, 5]
[]

empty?(t()) :: boolean()

Check if a value is the empty element of that type.

iex> empty?([])
true

iex> empty?([1])
false