Mac.sigil_m
You're seeing just the macro
sigil_m
, go back to Mac module for more information.
Specs
allows you to use the convenient ~m sigil to declare a Mac address in its normal string form, instead of using the tuple form.
iex> import Mac
iex> ~m"06:66:F4:12:34:56"
{0x06, 0x66, 0xF4, 0x12, 0x34, 0x56}