# <> operator allows the input parameters to be pattern matched

# input = "# This will be an h1"
# h = "#"
# t = "This will be an h1"
defp parse_header_tag(input = "#" <> _) do
  [h|t] = String.split(input)
  construct_header(String.length(h), Enum.join(t, " "))
end

# input = "__This will be bold__"
defp parse_header_tag(input) do

end

# String.replace
"__This will be bold__" |> String.replace(~r/__([^_]+)__/, "") -> ""
"__This will be bold__" |> String.replace(~r/__([^_]+)__/, "<strong>\\1</strong>")