Lukas Feiler wrote:
> Hi,
>
> Alexey Borzov wrote:
>
>> Hi,
>>
>> Lukas Feiler wrote:
>>
>>> A couple of days ago I proposed the package
PEAR_Callback;
>>> see http://pear.php.net/pepr/pepr-proposal-show.php?id=468
>>>
>>> It addresses three major limitations of the
callback pseudo-type:
>>> - By looking at a callback pseudo-type variable
you
>>> cannot tell if it really is a callback.
>>> - The callback pseudo-type does not allow you
to specify
>>> arguments at the time you create the
callback.
>>> - There is no way to force a user to pass only
callback
>>> functions to your API, that meet certain
requirements
>>> (i.e. accept certain arguments and have a
certain
>>> return type)
>>>
>> All of these major limitations can be overcome by
using the
>> Command design pattern:
>> http://e
n.wikipedia.org/wiki/Command_pattern
>>
>> I don't honestly see the benefit for PEAR in adding
a wrapper
>> around functions
>> when all these checks are already available for
classes /
>> objects in PHP5.
>>
>>
>
> PEAR_Callback effectively is a general command pattern
implementation - it
> eliminates the need to write a command class for every
callback function a
> programmer wants to use.
>
> But I do get your point. After all, OO languages like
Java don't even have
> something like call_user_func().
>
> Cheers,
> Lukas
>
I'm still a fan of the code. I think callbacks are
underused in PHP,
just because the java approach is what you find in books
doesn't mean
its the best approach for php.
-josh
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