sig seems to be broken for recursive functions

[kamentomov]

Here is an example:

(sig f2 (Fn [Char] Char))

(defn f2 [arg]
  (if (= arg \z)
    (f2 \z)
    \n))

This is the error:

I’m unable to concretize the expression '(meta-stub f2)' at line 0, column 0 in 'dummy-file'.

It might be too general. You could try adding a type hint using `the`. at conv.carp:14:2.

Traceback:
  (defn f2 [arg] (if (= arg \z) (f2 \z) \n)) at conv.carp:14:1.
(reload) at REPL:3:5.
(do (reload) (build)) at REPL:3:1.

A similar issue had been discussed here: #1213