Touche, Tom. Regarding my proposal…kill it with fire.

Kyle

> On Jun 27, 2019, at 2:11 PM, Tom Honermann <tom_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
>
>