# IsByRef() [v1.1.01+]

Returns a non-zero number if the specified ByRef parameter was supplied with a variable.

    TrueOrFalse := IsByRef(ParameterVar)

## Parameters

ParameterVar

  A reference to the variable. For example: `IsByRef(MyParameter)`.

## Return Value

This function returns 1 if ParameterVar is a ByRef parameter and the caller supplied a variable; or 0 if ParameterVar is any other kind of variable.

## Related

ByRef parameters

## Examples

#1

    MsgBox, % Function(MyVar)

    Function(ByRef Param)
    {
        return IsByRef(Param)
    }