Hello,

I'm working on an event system, and I want to be able to check if an event is a subclass of another event. How might I go about this? In essence, I'm looking to compress this:

static if (E == UserInputEvent || E == MouseEvent || E == MouseButtonEvent || E == MouseReleasedEvent)
{
    //MouseEvent => MouseButtonEvent => MouseReleasedEvent
    mreListeners[mrePtr] = listener;
    mrePtr++;
}

into something like this:

static if (isSuperclassOf!(MouseReleasedEvent, E))
{
    mreListeners[mrePtr] = listener;
    mrePtr++;
}

Thank you for your time.

-S

On 05/01/16 5:37 PM, Straivers wrote:
> Hello,
>
> I'm working on an event system, and I want to be able to check if an
> event is a subclass of another event. How might I go about this? In
> essence, I'm looking to compress this:
>
> static if (E == UserInputEvent || E == MouseEvent || E ==
> MouseButtonEvent || E == MouseReleasedEvent)
> {
>      //MouseEvent => MouseButtonEvent => MouseReleasedEvent
>      mreListeners[mrePtr] = listener;
>      mrePtr++;
> }
>
> into something like this:
>
> static if (isSuperclassOf!(MouseReleasedEvent, E))
> {
>      mreListeners[mrePtr] = listener;
>      mrePtr++;
> }
>
> Thank you for your time.
>
> -S

is(E : UserInputEvent)

On Tuesday, 5 January 2016 at 04:41:45 UTC, Rikki Cattermole wrote:
> On 05/01/16 5:37 PM, Straivers wrote:
>> Hello,
>>
>> I'm working on an event system, and I want to be able to check if an
>> event is a subclass of another event. How might I go about this? In
>> essence, I'm looking to compress this:
>>
>> static if (E == UserInputEvent || E == MouseEvent || E ==
>> MouseButtonEvent || E == MouseReleasedEvent)
>> {
>>      //MouseEvent => MouseButtonEvent => MouseReleasedEvent
>>      mreListeners[mrePtr] = listener;
>>      mrePtr++;
>> }
>>
>> into something like this:
>>
>> static if (isSuperclassOf!(MouseReleasedEvent, E))
>> {
>>      mreListeners[mrePtr] = listener;
>>      mrePtr++;
>> }
>>
>> Thank you for your time.
>>
>> -S
>
> is(E : UserInputEvent)

Okay, maybe I didn't write enough. I have multiple subtypes like:

static if (E == UserInputEvent || E == MouseEvent || E == MouseMovementEvent)
        { //MouseMovementEvent is a subclass of MouseEvent
            mmeListeners[mmePtr] = listener;
            mmePtr++;
        }
        static if (E == UserInputEvent || E == MouseEvent || E == MouseButtonEvent || E == MouseReleasedEvent)
        { //MouseEvent => MouseButtonEvent => MouseReleasedEvent
            mreListeners[mrePtr] = listener;
            mrePtr++;
        }
        static if (E == UserInputEvent || E == MouseEvent || E == MouseButtonEvent || E == MousePressedEvent)
        { //MouseEvent => MouseButtonEvent => MousePressedEvent
            mpeListeners[mpePtr] = listener;
            mpePtr++;
        }

and I want to differentiate between them so that a UserInputEvent will cause all three blocks to be compiled, but a MouseMovementEvent will only cause the first block to be compiled. Sorry about that.

On 05/01/16 5:50 PM, Straivers wrote:
> On Tuesday, 5 January 2016 at 04:41:45 UTC, Rikki Cattermole wrote:
>> On 05/01/16 5:37 PM, Straivers wrote:
>>> Hello,
>>>
>>> I'm working on an event system, and I want to be able to check if an
>>> event is a subclass of another event. How might I go about this? In
>>> essence, I'm looking to compress this:
>>>
>>> static if (E == UserInputEvent || E == MouseEvent || E ==
>>> MouseButtonEvent || E == MouseReleasedEvent)
>>> {
>>>      //MouseEvent => MouseButtonEvent => MouseReleasedEvent
>>>      mreListeners[mrePtr] = listener;
>>>      mrePtr++;
>>> }
>>>
>>> into something like this:
>>>
>>> static if (isSuperclassOf!(MouseReleasedEvent, E))
>>> {
>>>      mreListeners[mrePtr] = listener;
>>>      mrePtr++;
>>> }
>>>
>>> Thank you for your time.
>>>
>>> -S
>>
>> is(E : UserInputEvent)
>
> Okay, maybe I didn't write enough. I have multiple subtypes like:
>
> static if (E == UserInputEvent || E == MouseEvent || E ==
> MouseMovementEvent)
>          { //MouseMovementEvent is a subclass of MouseEvent
>              mmeListeners[mmePtr] = listener;
>              mmePtr++;
>          }
>          static if (E == UserInputEvent || E == MouseEvent || E ==
> MouseButtonEvent || E == MouseReleasedEvent)
>          { //MouseEvent => MouseButtonEvent => MouseReleasedEvent
>              mreListeners[mrePtr] = listener;
>              mrePtr++;
>          }
>          static if (E == UserInputEvent || E == MouseEvent || E ==
> MouseButtonEvent || E == MousePressedEvent)
>          { //MouseEvent => MouseButtonEvent => MousePressedEvent
>              mpeListeners[mpePtr] = listener;
>              mpePtr++;
>          }
>
> and I want to differentiate between them so that a UserInputEvent will
> cause all three blocks to be compiled, but a MouseMovementEvent will
> only cause the first block to be compiled. Sorry about that.

static if (is(E : UserInputEvent) || is(E : MouseEvent) || is(E : MouseButtonEvent) || is(E : MousePressedEvent)) {
	//....
}

Huh, alright. Thanks.