Pe3s, are you talking about passing a string (a component name) as a constructor (a procedure)?
This is nosense.
Yo need to explain this better.
Well, the constructor can be done to some extend, but OP should mind that FPC is not a scripting language.
It is unusual to use such constructs.
The technique to use is to use {$if declared(variableName)} in combination with RTTI to get a class reference from which you can create an instance. Highly
NOT recommended, but that would work, I guess.