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D - help - class B forward reference of base class A - error

reply Ant <Ant_member pathlink.com> writes:
I have an
class B forward reference of base class A
error (at compilation)

obvious class B has "import A"

this is while compiling a third class C that has
import A
import B
C is on a different package.

Anybody knows what's going on?

thanks
(I had solved this yesterday by changing the imports and/or compilation order,
but because of a user error (me) I had to restore older backups
and now I'm stuck)
Aug 07 2003
parent Ant <Ant_member pathlink.com> writes:
In article <bguvnu$1gse$1 digitaldaemon.com>, Ant says...
class B forward reference of base class A

Here is what I found out: if A and B refer to C and B extends A and C refers to B then B must be compiled before A WidgetBase = A WidgetButton = B EventDispatcher = C ------------- file WidgetBase.d private import EventDispatcher; class WidgetBase { } ------------- file WidgetButton.d private import WidgetBase; private import EventDispatcher; class WidgetButton : WidgetBase { ) -------------- file EventDispatcher.d private import WidgetButton; class EventDispatcher { } -------------- file Makefile all: dmd -v \ WidgetButton.d \ WidgetBase.d \ EventDispatcher.d \ -c \ -I~/dmd/src/phobos action: rm *.o ; make ### no error ### compiling WidgetButton before WidgetBase result: dmd -v \ WidgetButton.d \ WidgetBase.d \ EventDispatcher.d \ -c \ -I~/dmd/src/phobos parse WidgetButton parse WidgetBase parse EventDispatcher semantic WidgetButton semantic WidgetBase semantic EventDispatcher semantic2 WidgetButton semantic2 WidgetBase semantic2 EventDispatcher semantic3 WidgetButton semantic3 WidgetBase semantic3 EventDispatcher code WidgetButton code WidgetBase code EventDispatcher ### error; ### compiling WidgetBase before WidgetButton ### means that EventDispatcher will process WidgetButton ### before WidgetButton is compiled if I try to compile WidgetBase before WidgetButton i.e. Makefile is: -------------- file Makefile all: dmd -v \ WidgetBase.d \ WidgetButton.d \ EventDispatcher.d \ -c \ -I~/dmd/src/phobos action: rm *.o ; make result: dmd -v \ WidgetBase.d \ WidgetButton.d \ EventDispatcher.d \ -c \ -I~/dmd/src/phobos parse WidgetBase parse WidgetButton parse EventDispatcher semantic WidgetBase WidgetButton.d: class WidgetButton forward reference of base class WidgetBase
Aug 08 2003