Mac.is_mac

You're seeing just the macro is_mac, go back to Mac module for more information.
Link to this macro

is_mac(mac_addr)

View Source (macro)

Specs

is_mac(any()) :: Macro.t()

checks to see if a value is a mac address.

usable in guards.

iex> Mac.is_mac({10, 0, 0, 1, 1, 1})
true
iex> Mac.is_mac(:foo)
false
iex> Mac.is_mac({0x100, 0, 0, 1, 1, 1})
false
iex> Mac.is_mac({10, 0, 0, 1, 1, 1, 1})
false