Re: C++ preferences (was: RFC: lalr1.cc: support move semantics)

[Akim Demaille]

Hi!

> Le 13 sept. 2018 à 13:13, Frank Heckenbach <address@hidden> a écrit :
> 
> Akim Demaille wrote:
> 
>>> I do admit I usually don't declare my local variables const though
>>> they often should be
>> 
>> I recently had to work on some piece of software with coroutines,
>> and known what variables are immutable was really reassuring.
> 
> I haven't done coroutines, but threads, and of course, everything
> that's exposed there, I make as const as possible. But that doesn't
> usually include local variables.

Local variables can be captured by lambdas and passed to coroutines.
In fact, I enjoyed so much ‘const’ on my variables, that I started
using a lot ‘IIFE’ (immediately invoked function expressions) to
be able to have this property more often.  E.g.

const auto context = [&]
  {
    auto res = elle::serialization::Context{};
    res.set<Doughnut*>(&this->doughnut());
    res.set<elle::Version>(
      elle_serialization_version(this->doughnut().version()));
    return res;
  }();


>> I now spread `const` for similar reason: help the reader.
> 
> I think it's double-edged. OT1H, when the reader is trying to
> understand the code in detail, it certainly helps; OT2H on casual
> quick reading, too much verbosity can distract, especially for code
> that is not that complex.

I agree.


> So as I said, with a more concise syntax,
> it would be a no-brainer to me, but as things are, I often prefer
> shorter code. (For a similar reason, I also prefer "i" to
> "FoobarLoopCounter"; short names are quicker to parse mentally, and
> with small scopes there's no big danger of forgetting what the
> variables are, and of course, as a mathematician I'm used to short
> index variable names anyway. :)

:)  Indeed :)

I agree short lived entities should have short names.  That’s
actually one benefit (the only one?) to have *.h and *.c files:
*.h files can expose intelligent meaningful names, while *.c can
use short names.

>> https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/const
> 
> But they don't have type declarations. ;)

Sure!  But that’s the kind of conciseness I would love.