Enforcing a type spec

[chulkilee]

Typespec is just annotation and not used at runtime (like @doc).

To raise an error at runtime - you may add guard to functions so that you get no match found error. There are a few libraries to add abstraction for generating typespec and guard…

See also:

Type annotations / better type specs/ merging guards and type annotations

Hi, elixir folks! I want to propose a better syntax for type specs: defmodule MyModule do use TDef tdef my_fun(x: integer, y: String) :: integer do 1 end end After compilation it should be equivalent to @spec definitions and so could be processed by dialyzer. Also, one can use make type annotations compile to guards too tdef f(l: list[integer]) do to be compiled into something like @spec f(l :: list(integer) def f(l) where is_list(l) do ... What do you think?

(you can see people in this thread there!)