To be honest, I'd prefer to see mandatory braces for all control statements.

My main preference would be neither of these things happening - but to me,
a change that makes code more uniform is preferable over a code that makes
errors easier to make for the sake of a couple of bytes.

On Thu, 27 Jun 2019, 20:11 Tom Honermann via Std-Proposals, <
std-proposals_at_[hidden]> wrote:

> void f1() // Oops, forgot ;
> void f2(); // Now a local declaration in the definition of f1().
>
> Tom.
>
> On 6/27/19 12:29 PM, Kyle Knoepfel via Std-Proposals wrote:
> > Here’s an idea I’ve been thinking about a lot regarding functions
> composed of a single statement, and I’d like your thoughts.
> >
> > Consider the following function (and associated enumeration):
> >
> > enum class person {alice, bob, david};
> > std::string_view greet(person const p)
> > {
> > switch(p) {
> > case person::alice: return “Hello Alice.”sv;
> > case person::bob: return “What’s up Bob?”sv;
> > case person::david: return “(Avoid eye contact)”sv;
> > }
> > }
> >
> > In such a case, where there is no function-local state, I argue that the
> outer braces should be unnecessary:
> >
> > std::string_view greet(person const p)
> > switch(p) {
> > case person::alice: return “Hello Alice.”sv;
> > case person::bob: return “What’s up Bob?”sv;
> > case person::david: return “(Avoid eye contact)”sv;
> > }
> >
> > Of course, once someone wants to introduce function-local variables that
> are otherwise not contained by the statement in the function, then braces
> are required:
> >
> > std::string greet(person const p)
> > std::string const salutation{“Hi “}; // Error! Two statements in
> non-braced function definition.
> > switch(p) {
> > case person::alice: return salutation + "Alice.”;
> > case person::bob: return salutation + “Bob.”;
> > case person::david: return “(Avoid eye contact)”;
> > }
> >
> > I also run into functions that are defined like:
> >
> > void print_results(std::vector<Result> const& results)
> > {
> > for (auto const& res : results) {
> > std::cout << res << ‘\n’;
> > }
> > }
> >
> > An arguably better approach would be to do something like:
> >
> > for_all(results, [](auto const& res){ std::cout << res << ‘\n’; });
> >
> > but I occasionally run into situations where it may be more convenient
> to keep the explicit for loop:
> >
> > void print_results(std::vector<Result> const& results)
> > for (auto const& res : results) {
> > std::cout << res << ‘\n’;
> > }
> >
> > Or consider the handling of simple member functions:
> >
> > template <typename T>
> > class my_dumb_pointer {
> > T* ptr_;
> > public:
> > T* get() const noexcept { return ptr_; } // vs
> > T* get() const noexcept return ptr_; // Simpler? Not sure.
> > };
> >
> > Function definitions with empty bodies would still require braces.
> >
> > Does this idea seem worth fleshing out? How difficult would it be for
> implementations to provide, if it was worthwhile?
> >
> > Thanks very much,
> > Kyle Knoepfel
>
>
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