Subject: Re: [boost] [Review] Boost.Endian mini-review
From: Peter Dimov (lists_at_[hidden])
Date: 2015-01-26 17:14:17
Olaf van der Spek wrote:
> Isn't overflow more like a logic error than a runtime error? An assert
> might make more sense.
It typically happens in a portion of the code that can already throw because
it deals with output to file. And if it were an assert, what would you do to
avoid it? The same the library would do, check the value and throw if it
doesn't fit. So the library just does for you what you'd have done anyway,
as a convenience.
As a more practical matter, users don't tend to like asserts when saving,
even if this would have been the theoretically sound thing to do. :-)
(For the reverse operation, where the bits are more than the value type can
represent, assert doesn't seem to make sense either because we don't control
the bits, which typically come from an external source.)
In all this I'm assuming the buffer types, BTW. I'm not sure if the same
logic would apply to the arithmetic types, because they have very different
use cases. Buffers are relatively straightforward - the bits are read from
file and the value is extracted, or the value is stored and the bits are
written - so it's easier to reason about the context in which they are used.
Arithmetics should probably just do on overflow whatever the underlying type
does.