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From: Ian Collins <ian-news@hotmail.com>
Newsgroups: comp.lang.c++
Subject: Re: Event handler in c++
Date: Wed, 15 Feb 2012 07:17:43 +1300
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.c++:14045

On 02/14/12 11:14 PM, 88888 Dihedral wrote:
> 在 2012年2月13日星期一UTC+8下午7时52分44秒，Robin Tucker写道：
>> I'm using a templated method to describe, dispatch and handle events
>> in an intuitive manner. For example, describing an event can be done
>> with something like this:
>>
>>      Event<void(std::shared_ptr<Observable>, double, double, double)>
>> MyEvent;
>>
>> , for an event that takes 4 parameters (the "sender" and three
>> doubles). The handler looks like this:
>>
>>      void OnEventHandler(std::shared_ptr<Observable>  sender, double x,
>> double y, double z)
>>      {
>>          // Handle the event.
>>      }
>>
>> And the event is dispatched in the following intuitive way:
>>
>>      MyEvent(shared_from_this(), 3, 2, 1);
>>
>> It's type-safe and you can dispatch any number of parameters (up to 9
>> actually, in the absence of variadic templates in VS2010!). Anyway the
>> code and blog about it can be found here:
>>
>>      http://drrobsjournal.blogspot.com/
>>
>> I hope this is useful to someone.
>
> C++ is not very good to be usd as a language to
> write device drives to be called by the OS.

Yes it is, you just have to provide the OS hooks as extern "C" functions.

> People working on the linux kernal talked about this
> problem for so long.

They are somewhat bigoted.

> Unless functions in the C++ container and template libraries are incorporated into the OS kernal library
> or system shared  linked libraries,  otherwise  C++ compiled  programs are too fat in the heap, too.

"too fat in the heap" ?

In kernel space you have two choices:

1) Use C++ as a better C and avoid the parts that require runtime support.

2) Use a statically linked run time library.

I use one where resources are tight and 2 where they are not.

-- 
Ian Collins