Re: const element type in standard library containers
On May 30, 6:27 am, Ian Collins <ian-n...@hotmail.com> wrote:
No, you get away with it because the insert operation isn't
doing an assignment.
You don't get away with anything. Violating the requirements is
undefined behavior. An implementation is not required to
diagnose it, but it isn't required to document what happens if
there is no diagnostic. The code is wrong, and should be
corrected, even if your tests today don't show any problems.
I think that's what I said.....
You said that even if the tests show that the code works...:-)
Ah but I would have added a test for insert of an immutable
object!
Which might pass, even though the code is wrong. Undefined
behavior means that tests are meaningless, and IMHO, the problem
*isn't* with the concept of testing.
The "meaningless" is obviously hyperbole. But the presence of
undefined behavior in C++ does make reliable software
significantly more difficult, since it reduces the significence
of tests: you can never be sure that the test didn't pass just
because some undefined behavior happened to work this time.
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