Path: news.daimi.aau.dk!news.uni-c.dk!sunic!sunic.sunet.se!news.kth.se!nac.no!ifi.uio.no!nntp!alfh
From: alfh@byleist.ifi.uio.no (Alf-Ivar Holm)
Newsgroups: comp.lang.beta
Subject: Re: Sub Class generates linker error
Date: 21 Apr 1995 13:29:06 GMT
Organization: Dept. of Informatics, University of Oslo, Norway
Lines: 58
Message-ID: <ALFH.95Apr21152906@byleist.ifi.uio.no>
References: <3n6lb7$g96@pulm1.accessone.com>
NNTP-Posting-Host: byleist.ifi.uio.no
In-reply-to: Baiss E. Magnusson's message of 20 Apr 1995 21:56:55 GMT
CC: 

In article <3n6lb7$g96@pulm1.accessone.com> Baiss E. Magnusson <BMagnusson@PrecisionImages.com> writes:

> I am doing something wrong with creating a sub-pattern of the sub-pattern
> <myEventHandler> of the file <sample.bet>. I get a linker error, not a
> compiler error, as shown below.

The linker error/warning is caused by your 'myEventHandler', it has no
'do' part with an INNER (neither has 'eventHandler' in the libraries).
The do part of 'DoEditMenu' will not be done.

> I would like to call the sub-pattern <DoEditMenu> from wherever, and in
> the example below from within the pattern <menuSelected>, which is inside
> the superpattern.
> What syntax would correctly do what I need to do?

You have already figured out this one.

> 	myEventHandler : eventHandler 
> 	(#
> 			menuSelected ::< 
> 		(# 
> 			do 
> 				(if menu
> 					//editId then item -> DoEditMenu;
> 				if);
> 		#);
> #)
> 
> DoEditMenu: myEventHandler
>   (# item: @integer;
>   enter item
>   do
>  ...
>   #)
> ***** The superpattern of this descriptor has no INNER

I am not sure what you want to do, but you seem to go a bit over the
top about sub-patterns :-)  

The 'eventHandler'-patterns in the libraries are virtual patterns that
are instantiated by 'theEventHandler', which is called from other
patterns in the libraries.  The 'eventHandler' has no 'do' part, it
is just a pattern that 'Encapsulates the patterns related to
eventhandling'.  (Copied from guienv.bet :-)

When you make a sub-pattern of 'eventHandler', that sub-pattern have
to be called by your own (sub-)patterns to get instantiated.  If you
want your own 'eventHandler' to be called by the library patterns, it
is easiest to make a further binding of the 'eventHandler', ala:

	eventHandler ::
	(# menuSelected ::< (# ... #);
	   ...
	#)

Hope this helps.

	Affi