Re: How to overload == for System.Double

 Even if you could do this it is probably a really bad idea. Instead I
suggest you write a separate function 

Static bool Equallish(doubl lhs,double rhs)

Andrew

-----Original Message-----
From: Discussion relating to the specifics of the C# and Managed C++
languages [mailto:[email protected]] On Behalf Of Jack Brown
Sent: Thursday, February 01, 2007 3:33 PM
To: [email protected]
Subject: [DOTNET-CX] How to overload == for System.Double

Is it possible?

If I put these in a project:

                public static bool operator ==( double lhs, double rhs )
                {
                }
                public static bool operator !=( double lhs, double rhs )
                {
                }

I get a compiler error: One of the parameters of a binary operator must
be the containing type

I get this since the overloads are inside a class so they need to have
parameters that are of the containing class type. My problem is that I
can't put the operator overloads outside a class.

The reason I'm doing this is that I want to avoid the problems
associated with exact equality comparisons of floating point numbers. I
plan/wish to add a Math.Abs(lhs-rhs) <= epsilon where epsilon is some
suitably small value.

Any help, or at least confirmation that I can't do what I'd like to
would be appreciated.

--
Jack Brown
Controls Engineer
Electroimpact, Inc.
Desk: 425-609-4988
Cell: 206-617-6482
Office: 425-348-8090
[email protected]

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