Re: Impossible problem? A protected buffer to queue objects of a class-wide type

[Jean-Pierre Rosen <rosen@adalog.fr>]

Phil Slater a �crit :
> I've hit a brick wall. Every strategy I try doesn't work.
> 
> I need to write a generic package that exports a protected queue type that 
> will act as a buffer for objects of a class-wide type.
[...]
Interesting question ;-)

It should be solvable by separating the buffer from the protection, i.e. 
keep a protected object just as a lock, and provide operations that take 
the lock, do whatever is needed (possibly with several calls), then 
release the lock. Don't forget to have a "when others" exception handler 
to release the lock in case of an unexpected exception.

This should be quite easy to do if the buffer is the package (i.e. an 
abstract state machine). If you need to make the buffer an abstract data 
type, you'll have to put the protected object as a component of the record.

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            J-P. Rosen (rosen@adalog.fr)
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