             "genericsFunc { (↓a: Type, ↓b) -> Void in\n}\n":
                 "genericsFunc { (_: Type, _) -> Void in\n}\n",
             "genericsFunc { (a: Type, ↓b) -> Void in\nreturn a\n}\n":
-                "genericsFunc { (a: Type, _) -> Void in\nreturn a\n}\n"
+                "genericsFunc { (a: Type, _) -> Void in\nreturn a\n}\n",
+            "hoge(arg: num) { ↓num in\n}\n":
+                "hoge(arg: num) { _ in\n}\n"
         ]
     )
 

            "var label: UILabel = { (lbl: UILabel) -> UILabel in\n" +
            "   lbl.backgroundColor = .red\n" +
            "   return lbl\n" +
            "}(UILabel())\n"
        ],
        triggeringExamples: [
            "[1, 2].map { ↓number in\n return 3\n}\n",

            "[1, 2].map { ↓number in\n return 3 // number\n}\n",
            "[1, 2].map { ↓number in\n return 3 \"number\"\n}\n",
            "[1, 2].something { number, ↓idx in\n return number\n}\n",
            "genericsFunc { (↓number: TypeA, idx: TypeB) in return idx\n}\n",
            "hoge(arg: num) { ↓num in\n" +
            "}\n"
        ],
        corrections: [
            "[1, 2].map { ↓number in\n return 3\n}\n":
