Function std.checkedint.Checked.opUnary
Defines unary operators +, -, ~, ++, and --. Unary + is not
overridable and always has built-in behavior (returns this). For the
others, if Hook defines hookOpUnary, opUnary forwards to Checked!(typeof(hook.
auto opUnary(string op, _)()
if (op == "+" || op == "-" || op == "~");
ref Checked opUnary(string op)()
if (op == "++" || op == "--");
If Hook does not define hookOpUnary but defines onOverflow, opUnary
forwards to hook in case an overflow occurs.
For ++ and --, the payload is assigned from the result of the call to
onOverflow.
Note that unary - is considered to overflow if T is a signed integral of
32 or 64 bits and is equal to the most negative value. This is because that
value has no positive negation.
Parameters
| Name | Description |
|---|---|
| op | The unary operator |
Returns
A Checked instance representing the result of the unary
operation
Example
static struct MyHook
{
static bool thereWereErrors;
static L hookOpUnary(string x, L)(L lhs)
{
if (x == "-" && lhs == -lhs) thereWereErrors = true;
return -lhs;
}
}
auto a = checked!MyHook(long