Pattern, Abstract Factory / Factory

[Scott McKay]

Nobody in the list community ever invented a fancy pants term like “dependency injection”
because it’s so obvious how to do this that nobody thought to give it a name.

—Scott

> On Feb 6, 2021, at 4:07 PM, Manfred Bergmann <manfred.bergmann at me.com> wrote:
> 
> 
> 
>> Am 06.02.2021 um 21:44 schrieb Luís Oliveira <luismbo at gmail.com>:
>> 
>>> On Sat, 6 Feb 2021 at 20:07, Rudi Araújo <rudi.araujo at gmail.com> wrote:
>>> Class::newInstance() doesn't have any parameters (also, it's deprecated: better to use getConstructor() or getDeclaredConstructor() and call newInstance() on it).
>> 
>> I guess this bit about getConstructor() explains why it'd be more
>> convenient to use a Factory, or the Factory method pattern, or some
>> dependency injection framework.
>> 
> 
> Yeah. Could be.
> But this constructor thingy could be hidden in a function similar as you would create a constructor function make-foo in Common Lisp.
> The reflection stuff is not considered a good practice in certain types of applications.
> 
> Dependency injection is about something else IMO. Well, Abstract Factory is about it, too, inversion of control.
> It allows you to create something without having to know the concrete type and without having to have a source dependency on it.
> In Common Lisp this could be solved easily by just separating a protocol from the implementation, maybe in separate packages.
> 
> 
> 
> Manfred