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Subject: Re: [boost] [exception] ostringstream like
From: Stewart, Robert (Robert.Stewart_at_[hidden])
Date: 2010-10-19 14:56:17

[I just noticed this in my drafts folder.]

Fabien Castan wrote:
> > No, I mean that if you do advanced string manipulation in
> > the exception
> > itself, you may screw up, adn cause a bad_alloc beign
> > thrown and masking your own exception.
> Create an error sentence with some values inside is not really an
> advanced string manipulation.

The proposed message construction may not involve advanced string manipulation, by some definition of "advanced," but what you propose is non-trivial and involves a good deal of free store (de)allocation. It is far better to store state that can be used to produce an error message at the point the message is wanted. Otherwise, the risk is of doing work to produce a message that may not be needed, while adding the risk of exhausting memory.

Adding an insertion operator is likely to make formatting messages too easy in contexts where code should be concerned with simply storing state for consumption elsewhere. Thus, it would encourage bad practice.

Rob Stewart robert.stewart_at_[hidden]
Software Engineer, Core Software using std::disclaimer;
Susquehanna International Group, LLP

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