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+(+Number1, +Number2, -Result)

Evaluates the sum Number1 + Number2 and unifies the resulting value with Result.
Number1
A number.
Number2
A number.
Result
A variable or a number.

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

Exceptions

(4) instantiation fault
Number1 or Number2 is not instantiated (non-coroutining mode only).
(24) number expected
Number1 or Number2 is not of a numeric type.

Examples

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



See Also

is / 2