• =?UTF-8?B?TcOhcmNpbw==?= Martins (19/19) May 23 2018 Hi, recently we tried to upgrade DMD from 2.078.3 to 2.080 and
• ag0aep6g (3/26) May 23 2018 In the changelog:
• =?UTF-8?B?TcOhcmNpbw==?= Martins (4/32) May 23 2018 Wow! I don't know I missed it!
• Jonathan M Davis (13/47) May 23 2018 It would have, but there is literally no way to put it through the
• =?UTF-8?B?TcOhcmNpbw==?= Martins (2/3) May 23 2018 Got it! Thanks!
• Steven Schveighoffer (4/8) May 23 2018 Note, you could create an isSomeStringOrEnum template that does the old

=?UTF-8?B?TcOhcmNpbw==?= Martins <marcioapm gmail.com> writes:

Hi, recently we tried to upgrade DMD from 2.078.3 to 2.080 and 
found an unexpected semantic change.

Consider this program:

import std.traits;
enum X { Y = "z" };
alias T = typeof(X.Y);

pragma(msg, is(T == enum));
pragma(msg, isSomeString!T);
void main() {}`

Output in DMD <= 2.078.3:
true
true

Output in DMD >= 2.079.0:
true
false

This silent change is really nasty, and causing all sorts of 
breakages.
Was this a bug-fix, and if so, should we expect the new behavior 
to stick?

ag0aep6g <anonymous example.com> writes:

On 05/23/2018 11:21 AM, Márcio Martins wrote:
 Hi, recently we tried to upgrade DMD from 2.078.3 to 2.080 and found an 
 unexpected semantic change.
 
 Consider this program:
 
 import std.traits;
 enum X { Y = "z" };
 alias T = typeof(X.Y);
 
 pragma(msg, is(T == enum));
 pragma(msg, isSomeString!T);
 void main() {}`
 
 Output in DMD <= 2.078.3:
 true
 true
 
 Output in DMD >= 2.079.0:
 true
 false
 
 This silent change is really nasty, and causing all sorts of breakages.
 Was this a bug-fix, and if so, should we expect the new behavior to stick?

In the changelog:

https://dlang.org/changelog/2.079.0.html#std-traits-issomestring

=?UTF-8?B?TcOhcmNpbw==?= Martins <marcioapm gmail.com> writes:

On Wednesday, 23 May 2018 at 09:26:48 UTC, ag0aep6g wrote:
 On 05/23/2018 11:21 AM, Márcio Martins wrote:
 Hi, recently we tried to upgrade DMD from 2.078.3 to 2.080 and 
 found an unexpected semantic change.
 
 Consider this program:
 
 import std.traits;
 enum X { Y = "z" };
 alias T = typeof(X.Y);
 
 pragma(msg, is(T == enum));
 pragma(msg, isSomeString!T);
 void main() {}`
 
 Output in DMD <= 2.078.3:
 true
 true
 
 Output in DMD >= 2.079.0:
 true
 false
 
 This silent change is really nasty, and causing all sorts of 
 breakages.
 Was this a bug-fix, and if so, should we expect the new 
 behavior to stick?

 In the changelog:

 https://dlang.org/changelog/2.079.0.html#std-traits-issomestring

Wow! I don't know I missed it!

I would expect something like this to go through the deprecation 
process as it effectively silently breaks a ton of code.

Jonathan M Davis <newsgroup.d jmdavisprog.com> writes:

On Wednesday, May 23, 2018 09:31:35 Márcio Martins via Digitalmars-d wrote:
 On Wednesday, 23 May 2018 at 09:26:48 UTC, ag0aep6g wrote:
 On 05/23/2018 11:21 AM, Márcio Martins wrote:
 Hi, recently we tried to upgrade DMD from 2.078.3 to 2.080 and
 found an unexpected semantic change.

 Consider this program:

 import std.traits;
 enum X { Y = "z" };
 alias T = typeof(X.Y);

 pragma(msg, is(T == enum));
 pragma(msg, isSomeString!T);
 void main() {}`

 Output in DMD <= 2.078.3:
 true
 true

 Output in DMD >= 2.079.0:
 true
 false

 This silent change is really nasty, and causing all sorts of
 breakages.
 Was this a bug-fix, and if so, should we expect the new
 behavior to stick?

 In the changelog:

 https://dlang.org/changelog/2.079.0.html#std-traits-issomestring

 Wow! I don't know I missed it!

 I would expect something like this to go through the deprecation
 process as it effectively silently breaks a ton of code.

It would have, but there is literally no way to put it through the
deprecation process without deprecating isSomeString and replacing it with
something else, which would have broken tons of code. There is no way to
just deprecate the behavior. It was determined that it was unlikely that
much code would break and that it would in turn fix quite a bit of code and
prevent further bugs that the old behavior encouraged. And in general, the
fixes should be easy, since in most cases, it results in a compilation error
and then a quick fix to a template constraint or static if to get the old
behavior back if it was indeed intentional and not a bug. We would like to
have handled it better, but there really wasn't a better way given the
options.

- Jonathan M Davis

=?UTF-8?B?TcOhcmNpbw==?= Martins <marcioapm gmail.com> writes:

On Wednesday, 23 May 2018 at 09:43:28 UTC, Jonathan M Davis wrote:
 [...]

Got it! Thanks!

Steven Schveighoffer <schveiguy yahoo.com> writes:

On 5/23/18 11:31 AM, Márcio Martins wrote:
 On Wednesday, 23 May 2018 at 09:43:28 UTC, Jonathan M Davis wrote:
 [...]

 
 Got it! Thanks!

Note, you could create an isSomeStringOrEnum template that does the old 
behavior, and just do a sed 's/isSomeString!/isSomeStringOrEnum!/g'

-Steve