Question

I have a specific class C and I would like to overload some math operators.

I already overloaded +, i, *, and / so that I can do things like

a = C.new
b = C.new
a + b
a + 2
a + 2.0

To treat the last three cases, I am systematically testing for the type of the operand: is it C, Fixnum or Float, other possibilities are rejected. My first question is: is it the right way to do that?

Next I also want to be able to do

2.0 + A

How should I do it? Should I provide a conversion of some sort? Can these two problems be solved by the same method?

Answer 1

I believe the answer to “ruby operator overloading question” addresses both your points by using is_a? and coerce.

With regards to your first point. The normal approach in Ruby is to use respond_to? where possible, rather than checking for type. If for some reason you specifically need to check for type, then using is_a? is the correct way.