binary_parse_fast.exs

# For binary 0000 0001 0100 0000 1000 1000
# The result is 0b1 + 0b100_0000 + 0b1000 = 73
defmodule BinaryParseFast do
  def parse(bin) do
    parse(bin, 0)
  end

  # A byte beginning with 0 means the end, but still need to add the last 7 bits
  def parse(<<0::1, x::7, _::bits>>, acc), do: acc + x
  # A byte beginning with 1 means there is more data needed to be processed.
  # and we need to add the last 7 bits
  def parse(<<1::1, x::7, rest::bits>>, acc) do
    parse(rest, acc + x)
  end
end