如何在 elixir 中输入规格符号？

Question

the code was edited after the answer of Aleksei Matiushkin to include the @type

I'm trying to typespec a sigil specifically a Regex sigil but the current elixir doc don't specify how.

My code is close of:

defmodule M do
  @type pattern :: ??
  @type input :: String.t()
  @type current :: non_neg_integer()

  def tokenize_pattern(pattern, input, current) do
    # ...
  end
end

iex> M.tokenize_pattern(~r/[0-9]/u, "123 hello", 0)

Answer 1

Sigil ~Z is just syntactic sugar for sigil_Z macro, one even might define their own sigils, so their types are implementation-specific.

Both ~r and ~R sigils return the escaped result of a call to Regex.compile!/2 which is apparently Regex.t() .

---

Sidenote: your code would not compile. You probably wanted to define @spec fot the function as

  @spec (pattern :: Regex.t(),
         input :: String.t(),
         current :: non_neg_integer()) :: any()
  def tokenize_pattern(pattern, input, current) do
    # ...
  end
end