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# integer(+Number, -Result)

Convert an integral number of any type to an integer

Number
  A number.
Result
  Output: integer.

## Description

This predicate is used by the ECLiPSe compiler to expand evaluable arithmetic expressions. So the call to integer(Number, Result) is equivalent to

        Result is integer(Number)

which should be preferred for portability.

This is a pure type conversion operation. If Number has an integral value of any type, Result is that same value, but represented as an integer. If Number does not have an integral value, an exception is raised. This function should therefore normally be applied to the result of one of the rounding operations floor, ceiling, round or truncate.

In coroutining mode, if Number is uninstantiated, the call to integer/2 is delayed until this variable is instantiated.

### Modes and Determinism

- integer(+, -) is det

### Exceptions

(4) instantiation fault
  Number is not instantiated (non-coroutining mode only).
(5) type error
  Number is of type breal.
(20) arithmetic exception
  Number is not integral.
(24) number expected
  Number is not of a numeric type.

## Examples

    Success:
        X is integer(5).			% gives X = 5
        X is integer(5.0).			% gives X = 5
        X is integer(5_1).			% gives X = 5
        X is integer(5.0__5.0).		% gives X = 5

    Error:
        X is integer(1.1, X).               % arithmetic exception
        X is integer(5_4, X).               % arithmetic exception
        X is integer(0.99__1.01, X).        % arithmetic exception

## See Also

is / 2, floor / 2, ceiling / 2, round / 2, truncate / 2