
+(+Number1, +Number2, -Result)

   Evaluates the sum Number1 + Number2 and unifies the resulting value with
Result.



Arguments
   Number1             A number.
   Number2             A number.
   Result              A variable or a number.

Type
   Arithmetic

Description
   This predicate is used by the ECLiPSe compiler to expand evaluable
   arithmetic expressions.  So the call to +(Number1, Number2, Result) is
   equivalent to

    Result is Number1 + Number2

    which should be preferred for portability.

   The result is of type breal if any of the arguments is a breal,
   else float if any of the arguments is a float, else rational if any
   of the arguments is a rational.  Only when both arguments are
   integers is the result an integer.


   In coroutining mode, if Number1 or Number2 are uninstantiated, the call
   to +/3 is delayed until these variables are instantiated.




Modes and Determinism
   +(+, +, -) is det

Exceptions
     4 --- Number1 or Number2 is not instantiated (non-coroutining mode    only).
     5 --- Result is of a different type than the evaluation result.
    24 --- Number1 or Number2 is not of a numeric type.
    24 --- Result is neither a number nor a variable.

Examples
   
Success:
      +(5, 2, 7).
      +(5, -2.0, 3.0).
Fail:
      +(1, 2, 7).
Error:
      +(A, 2, 6).             (Error 4).
      +(1, 2, 3.0).           (Error 5).
      +(7 - 4, 2, 3).         (Error 24).
      +(5, 2, r).             (Error 24).





See Also
   is / 2
