public FEELFnResult<Boolean> invoke(@ParameterName( "range" ) Range range, @ParameterName( "point" ) Comparable point) {
        if ( point == null ) {
            return FEELFnResult.ofError(new InvalidParametersEvent(Severity.ERROR, "point", "cannot be null"));
        }
        if ( range == null ) {
            return FEELFnResult.ofError(new InvalidParametersEvent(Severity.ERROR, "range", "cannot be null"));
        }
        try {
            boolean result = (range.getLowEndPoint().compareTo(point) < 0 && range.getHighEndPoint().compareTo(point) > 0) ||
                             (range.getLowEndPoint().compareTo(point) == 0 && range.getLowBoundary() == RangeBoundary.CLOSED) ||
                             (range.getHighEndPoint().compareTo(point) == 0 && range.getHighBoundary() == RangeBoundary.CLOSED);
            return FEELFnResult.ofResult( result );
        } catch( Exception e ) {
            // points are not comparable
            return FEELFnResult.ofError(new InvalidParametersEvent(Severity.ERROR, "point", "cannot be compared to range"));
        }
    }
@Test
    void invokeParamsCantBeCompared() {
        FunctionTestUtil.assertResultError( includesFunction.invoke(
                new RangeImpl( Range.RangeBoundary.CLOSED, "a", "f", Range.RangeBoundary.CLOSED ),
                new RangeImpl( Range.RangeBoundary.CLOSED,  1, 2, Range.RangeBoundary.CLOSED ) ), InvalidParametersEvent.class );
    }