Delegates - Value Type or Reference Type?

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Smithers - 26 Sep 2007 17:34 GMT

Are delegates value types or reference types? I was just pondering the fact
that delegates are immutable... Does this mean that they are value types and
not reference types?

Thanks.

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Ido Samuelson - 26 Sep 2007 17:37 GMT

strings are immutable also and they are not value types.
delegates are not value types. they can be null :-)

> Are delegates value types or reference types? I was just pondering the
> fact that delegates are immutable... Does this mean that they are value
> types and not reference types?
>
> Thanks.

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Peter Duniho - 26 Sep 2007 18:05 GMT

> Are delegates value types or reference types? I was just pondering the fact
> that delegates are immutable... Does this mean that they are value types and
> not reference types?

No, they are a reference type.

Immutable doesn't mean it has to be a value type. And something that is
a value type is not required to be immutable. The two often go
hand-in-hand, but they are not actually the same thing, and there are in
fact counter-examples of each in the .NET Framework (the String class,
for example).

Pete

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Jon Skeet [C# MVP] - 26 Sep 2007 19:00 GMT

> > Are delegates value types or reference types? I was just pondering the fact
> > that delegates are immutable... Does this mean that they are value types and
[quoted text clipped - 7 lines]
> fact counter-examples of each in the .NET Framework (the String class,
> for example).

The difference being that while immutable reference types are
reasonably common and perfectly reasonable, making value types mutable
is almost *always* a bad idea, and can result in some very confusing
behaviour!

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Michael Starberg - 26 Sep 2007 20:57 GMT

>> > Are delegates value types or reference types? I was just pondering the
>> > fact
[quoted text clipped - 9 lines]
>> fact counter-examples of each in the .NET Framework (the String class,
>> for example).

Peter:
I still miss the copy-on-write semantics for strings I loved in Delphi.
While I know C# and even .NET says strings are immutable,
Do you know if the CLR treats strings as smart?

I hope Nicholas Paldino reads this, as he'd be sure to know. =)

> The difference being that while immutable reference types are
> reasonably common and perfectly reasonable, making value types mutable
> is almost *always* a bad idea, and can result in some very confusing
> behaviour!

Hmm. Give me an example of when it would be almost a good idea. =)

- Michael Starberg

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Delegates - Value Type or Reference Type?

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