List.improper-question-mark

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Link to this function

improper?(list)

View Source (since 1.8.0)

Specs

improper?(maybe_improper_list()) :: boolean()

Returns true if list is an improper list. Otherwise returns false.

Examples

iex> List.improper?([1, 2 | 3])
true

iex> List.improper?([1, 2, 3])
false