RE: [boost] Re: Boost.Threads: Do we need all those mutexes?

From: Batov, Vladimir (Vladimir.Batov_at_[hidden])
Date: 2004-06-30 17:06:00

> Well, as you point out, try_lock is like a timed_lock with
> time = 0, and lock is like a timed_lock with time = infinity,
> so why not give timed_lock both lock() and try_lock()
> methods as shorthand notation for lock(m, t=0) and
> lock(m, t=infinity)?

[Batov, Vladimir] Because, in my view, it violates the fundamental (and
I think widely accepted) OO design principle (guideline?) that in simple
terms can be expressed as "one class, one responsibility". Names like
Bertrand Meyer, Herb Sutter and many others immediately come to mind.

We can either achieve that by having a universal lock (with timed_lock
as the basis) and shorthand notations in separate derived classes (lock,
timed_lock and try_lock) or by keeping those three completely unrelated
(probably at the expense of some code/functionality duplication). I am
personally leaning towards latter, as even though technically all three
concepts are related, from the user point of view they are distinct.

> The argument for try_lock not having a blocking lock() method,
> which you seem to stress more often, is much clearer; I'm much
> more inclined to agree with you there.

[Batov, Vladimir] Thank you. I feel that it is important that every
class does what it promises to do. No more, no less.