Keyword.put_new

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Link to this function

put_new(keywords, key, value)

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Specs

put_new(t(), key(), value()) :: t()

Puts the given value under key unless the entry key already exists.

Examples

iex> Keyword.put_new([a: 1], :b, 2)
[b: 2, a: 1]
iex> Keyword.put_new([a: 1, b: 2], :a, 3)
[a: 1, b: 2]