Manipulate bit flags in Elixir.
# Let's say we want to remember certain days of week as a single integer
iex> days_of_week = [:sunday, :monday, :tuesday, :wednesday, :thursday, :friday, :saturday]
# The number of bit flags
iex> size = 7
# All the days of the week are 127, no day of the week is the value 0
iex> state = 0b0000000
0
iex> BitFlagger.parse(state, size)
[false, false, false, false, false, false, false]
# Turn on the flags at index 1 (Monday) and 3 (Wednesday)
iex> state = state |> BitFlagger.on(1) |> BitFlagger.on(3)
10
iex> BitFlagger.parse(state, size)
[false, true, false, true, false, false, false]
# Turn off the flag at index 1 (Monday)
iex> state = BitFlagger.off(state, 1)
8
iex> BitFlagger.parse(state, size)
[false, false, false, true, false, false, false]
# We can easily make it human readable
iex> Enum.zip(days_of_week, BitFlagger.parse(state, size))
[
sunday: false,
monday: false,
tuesday: false,
wednesday: true,
thursday: false,
friday: false,
saturday: false
]Add bit_flagger to your list of dependencies in mix.exs:
def deps do
[
{:bit_flagger, "~> 0.1.0"}
]
endDocumentation can be found at https://hexdocs.pm/bit_flagger.