Re: [boost] More "any" remarks

From: Ed Brey (brey_at_[hidden])
Date: 2000-11-12 16:36:43

From: "David Abrahams" <abrahams_at_[hidden]>
>
> > and I cannot see what inadvertent implications you are referring to --
>
> For example, that other boost classes are not exception-safe.
>
> > all members satisfy the strong or no throw gtee (this might be worth
> > documenting).
>
> Yes! That at least has some value as information, wheras the statement
that
> it is exception-safe has (almost) none.

This discussion seems to be pointing to a need for a top-level "library
invariants" page that would list guarantees that are made for all boost
libraries.  Then each library would not need to repeat this information in
its page.  In this case, the invariant is that all libraries are exception
safe.  The page could describe the meaning of this and provide a definition
of the minimum weak guarantee that all boost libraries offer.  It can also
define the stronger guarantees so that individual libraries that offer
stronger guarantees can specify so in just a few words linked back to a full
definition of the guarantee.

If we don't have a centralized source on exception guarantees, the
alternatives are (1) potential duplicate descriptions of exception safety in
various libraries, (2) confusing end users who are not familiar with
exception safety, or (3) cross-referencing a description of exceptions
safety such as http://www.research.att.com/~bs/3rd_safe.pdf.

Nothing is coming to mind at the moment as far as other library invariants
go, but I suspect that they exist.  The "library invariant" concept is
similar to the existing Library Requirements and Guidelines, but with
different focus.  The Requirements are aimed at library developers, whereas
I'm proposing something directly geared towards end users in the form of
documentation common to all libraries.