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digitalmars.D - The forgotten deprecation: switch case fall-through

reply Bastiaan Veelo <Bastiaan Veelo.net> writes:
Hi,

Switch case fallthrough (non-empty cases that do not end with a 
break, continue, goto, return, throw or assert(0) statement) has 
been deprecated for more than 9 years [1]. As I am fixing a bug 
due to unintended case fall-through today, I am wondering when 
its deprecation period will be ended. It is not in the list of 
deprecations [2]. Does this mean that it is being forgotten? Is 
there a protocol for what should happen to deprecations and when, 
and who is taking care of that process?

Had there been a -preview switch for making this an error, I'd be 
using it (I can't use -de just yet, as I need to allow other 
deprecations for the moment).

Thanks,
Bastiaan.

[1] 
https://github.com/dlang/dlang.org/commit/ae093a0e416821768260da799fe565654f48a5d6
[2] https://dlang.org/deprecate.html
Dec 03 2020
parent reply kdevel <kdevel vogtner.de> writes:
On Thursday, 3 December 2020 at 09:29:12 UTC, Bastiaan Veelo 
wrote:

 Switch case fallthrough (non-empty cases that do not end with a 
 break, continue, goto, return, throw or assert(0) statement) 
 has been deprecated for more than 9 years [1]. As I am fixing a 
 bug due to unintended case fall-through today, I am wondering 
 when its deprecation period will be ended.


For the non-trivial ArgumentList case [1] it has not even startet 
yet

~~~switchbreak.d
int foo (string s)
{
    int a;
    switch (s) {
       case "eins", "zwei":
          a = 1;
       default: // no warning
    }
    return a;
}

int bar (string s)
{
    int a;
    switch (s) {
       case "eins": case "zwei":
          a = 2;
       default: // deprecation warning
    }
    return a;
}

unittest {
    assert (foo ("") == 0);
    assert (foo ("eins") == 1);
    assert (foo ("zwei") == 1);
    assert (bar ("") == 0);
    assert (bar ("eins") == 2);
    assert (bar ("zwei") == 2);
}
~~~

$ dmd -unittest -main -run switchbreak
switchbreak.d(18): Deprecation: switch case fallthrough - use 
'goto default;' if intended
1 unittests passed


[1] https://dlang.org/spec/statement.html#switch-statement
Dec 13 2020
parent Bastiaan Veelo <Bastiaan Veelo.net> writes:
On Sunday, 13 December 2020 at 20:45:55 UTC, kdevel wrote:

 On Thursday, 3 December 2020 at 09:29:12 UTC, Bastiaan Veelo 
 wrote:


[...]

 I am wondering when its deprecation period will be ended.


 For the non-trivial ArgumentList case [1] it has not even 
 startet yet

 ~~~switchbreak.d
 int foo (string s)
 {
    int a;
    switch (s) {
       case "eins", "zwei":
          a = 1;
       default: // no warning
    }
    return a;
 }


Oh dear!

— Bastiaan.
Dec 13 2020