import unittest proc concat(a, b): string = result = $a & $b test "if proc param types are not supplied, the params are assumed to be generic": check concat(1, "test") == "1test" check concat(1, 20) == "120" check concat("foo", "bar") == "foobar" test "explicit param types can still be specified": check concat[cstring, cstring]("x", "y") == "xy"