On Tuesday, 20 June 2017 at 11:57:55 UTC, Mike Parker wrote:
DIP 1009 is titled "Improve Contract Usability".
[...]
Veering a bit off topic,the compiler doesn't treat contracts any
different from other code, does it? For instance, consider:
int foo()
out(result; result>0)
{
// whatever
}
int bar(int x)
in (x<0)
{
// whatever
}
int main() {
return bar(foo());
}
I would have liked to get a *compile-time* error in case of such
a trivial contract violation. Of course, I don't expect the
compilier to try and prove that a contract holds (seems
unrealitic and not so useful) but it would be nice if it could at
least spot simple errors, like in the example above.
In a similar vein, the information conveyed in a contract can
potentially be used to apply simple optimizations, at least in
trivial cases.
If the contract system amounts to placing assertions at the
beginning and/or end of a function, it doesn't seem so useful
except for documentation and readability.
