On 08/04/2010 06:38 AM, Steven Schveighoffer wrote:
On Tue, 03 Aug 2010 17:56:44 -0400, Walter Bright
<newshou...@digitalmars.com> wrote:
bearophile wrote:
27.50, "transactional file copy": this example was script-like, and
as short
as possible to fit into one single slide, so in this case I think using
enforce() is OK. But in true programs I suggest all D programmers to use
DesignByContract with assert() more and to use enforce() less. Among
other
things enforce() kills inlining possibilities and inflates code. In
D.learn I
have seen people use enforce() in a situation where DbC is designed
for. I
think the D community needs to learn a bit more DbC, and in my
opinion to do
this the leaders have to lead the way.
There's a misunderstanding here. Contract programming is for detecting
program bugs. enforce() is for detecting and handling errors such as
disk failures and bad user input.
They are COMPLETELY DIFFERENT and must not be conflated.
Yes, but as has been discussed and resolved on phobos mailing list,
usage errors should not be handled via uncaught exceptions. I think the
example is flawed in that regard. I wouldn't bring it up, but people who
haven't followed that discussion might get the wrong idea from this
example.
Well I agree with the spirit but let me say this. If all I want is a
short script that does the right thing, I don't care whether failure
comes with a stack trace caboose. So I don't think the example is flawed
at all - it stands as a short correct script that does something useful.
Andrei
