RegExp.prototype is an ordinary object.

test/mjsunit/regress/regress-1217.js

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-
-// Check that RegExp.prototype is itself a RegExp object.
-
-var proto = RegExp.prototype;
-assertEquals("[object RegExp]", Object.prototype.toString.call(proto));
-
-assertEquals("(?:)", proto.source);
-assertEquals(false, proto.global);
-assertEquals(false, proto.multiline);
-assertEquals(false, proto.ignoreCase);
-assertEquals(0, proto.lastIndex);
-
-assertEquals("/(?:)/", proto.toString());
-
-var execResult = proto.exec("argle");
-assertEquals(1, execResult.length);
-assertEquals("", execResult[0]);
-assertEquals("argle", execResult.input);
-assertEquals(0, execResult.index);
-
-assertTrue(proto.test("argle"));
-
-// We disallow re-compiling the RegExp.prototype object.
-assertThrows(function(){ proto.compile("something"); }, TypeError);