On 08/20/2010 08:53 PM, Jonathan M Davis wrote:
On Friday, August 20, 2010 11:35:48 Nick Sabalausky wrote:
"bearophile"<bearophileh...@lycos.com> wrote in message
news:i4luk9$2rd...@digitalmars.com...
A small Reddit thread regarding if unused variables and imports are better
as errors or warnings:
http://www.reddit.com/r/programming/comments/d3emo
In my opinion in this case errors are too much, warning are enough.
Few situations for those warnings:
- warning for unused variables (as GC, C# and other compilers do);
- warning when a variable get used in some ways, and then its last
assignment gets unused (done by a kind of C compiler);
- unused imports (useful to keep code clean and remove unnecessary module
dependences);
- unused functions (but this is harder to do in a clean way in a language
that has templates, so this may be omitted).
Among those four warnings the most useful are the first two ones. In C
once the unused variable warning of GCC has found at compile time a bug
in my code (I did forget to increment that variable in the loop). So I
have loved this warning ever since.
An error would be an enormous pain in the ass. A warning might be helpful
in some cases.
Except that thanks to how warnings are deal with in dmd, there's not much
difference between an error and a warning; it's just a question of how picky you
want to be about errors. As it is, I'd argue that there is no such thing as a
real warning in D. You never see warnings unless you use -w, at which point
they're treated as errors. And if you're being at all careful, you're going to
be compiling with -w, so it doesn't make much difference. You can choose to
compile without -w until you think what you have works and then use -w to find
stuff you missed, but then you could easily be being shot in the foot by
something that's considered a warning. If you had seen it, you could have dealt
with it. What dmd needs is for warnings to be visible in normal compilation,
making -w only make warnings errors as opposed to being the way to make them
appear as well. As it is, warnings pretty much might as well be errors.
- Jonathan M Davis
I don't get this point of view.
I mean, either you care about them, in which case they may as well be
errors, or you don't care, in which case you don't need to see them at all.
When you insert a debug-ish early return, do you really want to see the
warning text every time you compile?
I think what dmd does is great. :-)
