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[Xotcl] Improvement proposal for instfilters and guards

From: Eckhard Lehmann <eckhardnospam_at_gmx.de>
Date: Tue, 27 May 2008 22:33:31 +0200

Hi all,

instfilters and -guards are great features in XOTcl. Nevertheless there
is room for improvement...

In 99% of the cases one (I at least) creates a filter that needs to be
triggered only at a certain method. Even if one has several methods to
intercept, it is often easier to create separate methods and use guards
to trigger them.
Guards are great, but the overall picture of the code gets overly
complicated in such cases. Therefore I'd like to propose an argument
"-methods" to the filter command, that tells the filter to only be
triggered on execution of the methods in the corresponding list:

Class A
...
A instproc do1 {} ...
A instproc do2 {} ...
A instproc do3 {} ...

A instproc do1Filter {} ...

# trigger only at do1
A instfilter do1Filter -methods do1 ;# or -methods {do1 do3}

# rather than
A instfilter do1Filter
A instfilterguard do1 {[string eq [self calledproc] do1]}

Is such a feature already planned? If not, is there anything that speaks
against it?


-- 
Eckhard