+                        Binary Addition operator

 exp1 + exp2             Binary arithmetic addition
 exp1                    any real or integer expression expression
 exp2                    any real or integer expression

    As a binary operator, + performs addition.  Examples:

           i  = 3223 + 88;      # i == 3311

-                        Binary Subtraction

 exp1 - exp2             Binary subtraction
 exp1                    any real or integer expression
 exp2                    any real or integer expression

    As a binary operator, - performs subtraction.  Examples:

           i = 3223 - 88;       # i == 3135
           x = 3.5 - 4.5;       # x == -1.0