On 05.03.2018 22:11, Walter Bright wrote:
On 3/5/2018 11:34 AM, Timon Gehr wrote:
On 05.03.2018 11:30, Walter Bright wrote:
The hints will usually not make a significant difference in
performance anyway.
Reasonable people will disagree on what is significant or not.
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My point exactly! Hence, compiler flag.
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I did not make the code any more wrong by adding the assertion.
Why should I get more UB?
Because you put in an assert that did not hold, and disabled the check.
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(Maybe let's assume it was not me who did it, to stop the whole silly
"you deserve what you got because you made a mistake" notion.)
Again, my question is not about the _mechanics_ of the status quo. I
know it very well. It's the rationale that matters.
Now we have the following options:
- Leave contracts in -- fail performance requirements.
- Remove contracts -- fail safety requirements.
- Track down all 'assert's, even those in external libraries, and
replace them by a custom home-cooked solution that is incompatible
with everyone else's -- fail maintainability requirements.
To me this situation is ridiculous.
It's completely under the control of the programmer. I know you disagree
with that notion.
I don't. I can use a manual patch of the compiler that has the
additionally required flags and replicate the official packaging effort
and make everyone who wants to compile my programs use that version. I
just don't want to, as it seems silly.
It would be a lot better if the standard DMD compiler had the flags. Do
you disagree that there should be an additional option to ignore
contracts completely?
You can even create your own `myassert` to produced
your desired semantics.
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That's the third option above. It's not a practical solution. Putting
the flag into a compiler fork is trivial by comparison.
FWIW, this is what all contract systems that I'm aware of do, except
D, and maybe C asserts in certain implementations (if you want to call
that contracts).
D is better (!).
(C's asserts are not part of the language, so impart no semantics to the
compiler.)
(That's why I said "in certain implementations".)
