List.keymember-question-mark

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Link to this function

keymember?(list, key, position)

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Specs

keymember?([tuple()], any(), non_neg_integer()) :: boolean()

Receives a list of tuples and returns true if there is a tuple where the element at position in the tuple matches the given key.

Examples

iex> List.keymember?([a: 1, b: 2], :a, 0)
true

iex> List.keymember?([a: 1, b: 2], 2, 1)
true

iex> List.keymember?([a: 1, b: 2], :c, 0)
false