RE: [PEAR-DEV] PEAR_Callback proposal

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://en.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