lib/lexical/text.ex
defmodule Lexical.Text do
def count_leading_spaces(str), do: count_leading_spaces(str, 0)
def count_leading_spaces(<<c, rest::binary>>, count) when c in [?\s, ?\t],
do: count_leading_spaces(rest, count + 1)
def count_leading_spaces(_, count), do: count
end