The two files (MathDD1.cs and MathDD2.cs) change the core Squeak mathematic functions (+, -, /, *) for the basic Number types (Integer, Fraction, and Float) to use double dispatching rather than coercion (though the current coercion is itself implemented as a form of double dispatch).

This change consists of two files, because the filein must be done in two steps. The first file (MathDD1.cs) ADDS all of the double dispatch methods to the base types. The second file (MathDD2.cs) CHANGES all of the math selectors to use the methods added with the first step. To intermix the two would've created the potential to crash the image. Needless to say, you MUST file in MathDD1.cs BEFORE MathDD2.cs.