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Re: const Object cannot receive messages in 10.4

If I try to send a message to a variable defined as const Object *, I get a warning: "warning: invalid receiver type 'Object *'". I'm currently fixing this by removing a bunch of "const" qualifiers from my code, but am curious as to what is causing the error and what has changed.

I'm surprised you ever got this working - Objective-C doesn't use the C++ style for immutable objects, but rather builds [im]mutability into class design. You'll rarely, if ever, actually want a const object, since you can't message it.

As an analogy, consider a const class reference in C++, and what happens when you call any method not qualified as "const" - it won't work, either. Objective-C has no equivalent "const" qualifier for methods, that I'm aware of.

I know from my own experience this didn't work on some previous version of MacOS X - 10.3 or possibly 10.2. Did you do anything unusual to get the compiler to accept it to start with?

Wade Tregaskis (AIM/iChat, Yahoo, Gizmo & Skype: wadetregaskis, ICQ: 40056898, MSN: email@hidden, AV iChat & email: email@hidden, Jabber: email@hidden)
-- Sed quis custodiet ipsos custodes?

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 >const Object cannot receive messages in 10.4 (From: Andrew White <email@hidden>)



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