Question

I’ve been messing with this bit of code for over an hour trying to rearrange it different ways. Is there any easier way to write it?

   if x is not Number      ;// if x is string
   {
      if y is not Number      ;// x, y both strings
      {
         Eval(x)
         Eval(y)
         return
      }
      else                    ;// x is string, y is Number
      {
         Eval(x)
         Scale(y)
         return
      }
   }
   else if y is not Number    ;// x is Number, y is string
   {
      Scale(x)
      Eval(y)
      return
   }
   else                       ;// both are numbers
   {
      Scale(x)
      Scale(y)
      return   
   }

Answer 1

It looks like you want to Eval strings and Scale numbers. Instead of having four explicit cases (which would become eight with three variables), handle each case for x and y independently:

if x is Number
    Scale(x)
else
    Eval(x)

if y is Number
    Scale(y)
else
    Eval(y)

Or, better yet, you can push Eval/Scale into a utility method:

ScaleOrEval(z):
    if z is Number
        Scale(z)
    else
        Eval(z)

…and then use it…

ScaleOrEval(x)
ScaleOrEval(y)

If you pick good method names, then creating a utility method makes the code more readable and helps you avoid copy-and-paste repetition.