The generics IComparable<T>

[TonyJ]

Hello!

I'm reading in a book from Microsoft that the generic interface
IComparabler<T> define the two methods
CompareTo and Equals.

Now to my querstion if I look in the docs it says that CompareTo is defined
in the IComparabler<T> but
the Equals is not mentioned.

Is this just a bad book telling me wrong thing?
Or do I misunderstand it in some way?

//Tony

 

[Jon Skeet [C# MVP]]

I'm reading in a book from Microsoft that the generic interface
IComparabler<T> define the two methods
CompareTo and Equals.

Now to my querstion if I look in the docs it says that CompareTo is defined
in the IComparabler<T> but
the Equals is not mentioned.

Is this just a bad book telling me wrong thing?
Or do I misunderstand it in some way?

Do you mean IComparer<T> or IComparable<T>? They are two different
interfaces, but there's no such thing as IComparabler<T>.

In either case though, there's no Equals method. That appears in
IEquatable<T> and IEqualityComparer<T>.

Jon

 

[Marc Gravell]

The book is wrong (or is being taken out of context; hard to tell
without a citation); it inherits a few methods from object (Equals(),
GetHashCode(), GetType() and ToString() ) but the interface itself
only declares CompareTo().

Marc

 

[Marc Gravell]

Frther; there is a "bool Equals(T other)", but that is on
IEquatable<T>

Marc

 

[Peter Sestoft]

I'm reading in a book from Microsoft that the generic interface
IComparabler<T> define the two methods
CompareTo and Equals.

Now to my querstion if I look in the docs it says that CompareTo is defined
in the IComparabler<T> but
the Equals is not mentioned.

An early design for the .NET 2.0 class library had Equals(T) on
IComparable<T>, but fortunately this was changed before release.

The book may have been written against that early design.

Peter