[fpc-devel] Interface delegation fix: backport to FPC 2.4.2 ...?

Graeme Geldenhuys graemeg.lists at gmail.com
Thu May 20 09:47:57 CEST 2010

Helmut Hartl het geskryf:
> Patterns are super -  but not if you are coding something performance 
> critical.

Then you are still struggling to understand design patterns. I'll say it
again: They are a design guide for solving a common found problem. How you
implement it, is up to you! Design patterns are all over the place
(Compiler, RTL, FCL, VCL, LCL etc) - maybe you [or any other developer]
simply didn't know that the solution implemented to solve a problem
actually had a name, and the structure of the solution was documented
before, with nice pretty UML diagrams.

> while coding our boring business stuff  multitier bloatet database 
> applications I would like the observer. (We did databases long enough
> now and switched to something more fun)

Observer has nothing to do with database applications. Neither does most of
the other well documented design patterns.

More examples of design patterns:

* TAction / TActionList - uses the Command pattern
* TAction in fpGUI - uses Command and Observer patterns
* Application, Screen variables used in VCL - a very crude Singleton pattern
* Compiler parsing code - probably uses the State pattern
* LCL deciding which backend library to use - a form of Abstract Factory
* Lazarus IDE list of available syntax highlighters - a form of Simple
Factory Method pattern

...the list goes on, and none of these are database related.

  - Graeme -

fpGUI Toolkit - a cross-platform GUI toolkit using Free Pascal

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