[antlr-interest] anybody get bitten by ANTLR's AST interfacerequirement

[Hill, Robert]

You can do this in C#2 I believe.
'Covariance' IIRC.



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Rob Hill
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>-----Original Message-----
>From: antlr-interest-bounces at antlr.org 
>[mailto:antlr-interest-bounces at antlr.org] On Behalf Of Martin Probst
>Sent: 24 January 2006 10:00
>To: antlr-interest at antlr.org
>Subject: Re: [antlr-interest] anybody get bitten by ANTLR's 
>AST interfacerequirement
>
>In code:
>
>class X { .. }
>class Y extends X { .. }
>
>class A {
>  X foo();
>}
>
>class B extends A {
>  Y foo(); // <-- !!!
>}
>
>The class B with the overriding foo() returning Y was not 
>possible before, and it can really enhance complicated APIs. 
>E.g. if you move down the API abstraction level you can now 
>have the more concrete classes also return more concrete 
>types, and that is nice.
>
>Martin
>
>