TypeScript/tests/cases/conformance/classes/members/inheritanceAndOverriding/derivedClassTransitivity4.ts
2014-09-23 11:22:38 -07:00

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TypeScript

// subclassing is not transitive when you can remove required parameters and add optional parameters on protected members
class C {
protected foo(x: number) { }
}
class D extends C {
protected foo() { } // ok to drop parameters
}
class E extends D {
public foo(x?: string) { } // ok to add optional parameters
}
var c: C;
var d: D;
var e: E;
c = e;
var r = c.foo(1);
var r2 = e.foo('');