ruby operator overloading question

Question

i\'ve been messing around with ruby and opengl for entertainment purposes, and i decided to write some 3d vector/plane/etc classes to pretty up some of the math.

simplif

Answer 1

Using coerce is a MUCH better approach than monkey-patching a core class:

class Vec3
    attr_accessor :x,:y,:z

    def *(a)
        if a.is_a?(Numeric) #multiply by scalar
            return Vec3.new(@x*a, @y*a, @z*a)
        elsif a.is_a?(Vec3) #dot product
            return @x*a.x + @y*a.y + @z*a.z
        end
    end

    def coerce(other)
        return self, other
    end
end

if you define v as v = Vec3.new then the following will work: v * 5 and 5 * v The first element returned by coerce (self) becomes the new receiver for the operation, and the second element (other) becomes the parameter, so 5 * v is exactly equivalent to v * 5