On Sun, 22 Sep 2024 16:56:47 +0100
Bart wrote:
> On 22/09/2024 16:11, Kaz Kylheku wrote:
> > On 2024-09-22, David Brown wrote:
> >> I am not suggesting overuse of braces. I am suggesting /good/ use
> >> of them.
> >>
> >>
> >>
> >> That's perhaps the most famous example of the havoc caused by
> >> omitting useful braces.
> >>
> >> Consistency and clarity is important. So is maintainability.
> >> Suppose, for example, you want to add a line "attempts++;"
> >> alongside the "ok++;" line. When the braces are there, the change
> >> is exactly that - add the new line you want. Without the original
> >> braces, you are now making changes to the structural syntax of the
> >> code as well when you add in original braces - or you are making a
> >> mistake in the code.
> >
> > My super advanced text editor from the future isn't letting me do
> > that:
> >
> > if (failed)
> > WARN("failed because...");
> > else
> > ok++;
> > attempts++; // automatic deindent
> >
> > When I add a line after ok++, it deindents it to be at the same
> > indentation level as the if, before letting me type any content
> > into it.
> >
> > OK, I lied about the super advanced from the future. It's just Vim.
> >
> > Also GCC has been able to diagnose misleading indentation for some
> > years now.
> >
> > Between those two, there is nothing to worry about; just
> > concentrate on whether it looks prettier without the braces or with.
> >
>
> So, everyone has to write code exactly to the C standard.
>
> But when it comes to more practical matters, it's OK to depend on the
> arbitrary characteristics and abilities of whichever one of 1001
> different text editors we happen to be using.
>
> Or we have to use a specific compiler with a specific set of options.
>
> > Also GCC has been able to diagnose misleading indentation for some
> > years now.
>
> How many years was that out of the last 52? How exactly do you turn
> it on? Since -Wall -Wpedantic -Wextra doesn't report it.
>
My gcc warns just fine.
void bar(int);
int foo(int x) {
if (x)
bar(x);
x -= 1;
return x;
}
gcc -c -Wall foo.c
foo.c: In function 'foo':
foo.c:3:3: warning: this 'if' clause does not guard...
[-Wmisleading-indentation] 3 | if (x)
| ^~
foo.c:5:5: note: ...this statement, but the latter is misleadingly
indented as if it were guarded by the 'if'
5 | x -= 1;
| ^
> It is a failure in the design of the language. You can't really
> depend on ad hoc features of the tools you use to create and compile
> source code.
>
> At least guidelines can be used such as always using braces, then
> errors can occur less often.
>
> (I've been bitten by this endless times when trying to add debugging
> statements to existing code. If that code consistently used braces,
> then it wouldn't happen.)
I wonder why I was not bitten by that more than, may be, 5 times in
30+ years. Probably, I am doing something wrong.
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