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digitalmars.D.learn - On Variable References

reply "Per =?UTF-8?B?Tm9yZGzDtnci?= <per.nordlow gmail.com> writes:
Why doesn't D allow declarations such as

     int x;
     auto ref xr;

?

What is so fundamentally bad about this compared to foreach 
variables and function arguments passed by reference?

Will Walters latest commits regarding

http://wiki.dlang.org/DIP25

change this matter?
Jan 21 2015
parent reply "Per =?UTF-8?B?Tm9yZGzDtnci?= <per.nordlow gmail.com> writes:
On Wednesday, 21 January 2015 at 08:22:44 UTC, Per Nordlöw wrote:

     int x;
     auto ref xr;


Correction: I, of course mean,

     int x = 42;
     auto ref xr = x;
Jan 21 2015
parent reply "Meta" <jared771 gmail.com> writes:
On Wednesday, 21 January 2015 at 08:23:44 UTC, Per Nordlöw wrote:

 On Wednesday, 21 January 2015 at 08:22:44 UTC, Per Nordlöw 
 wrote:

    int x;
    auto ref xr;


 Correction: I, of course mean,

     int x = 42;
     auto ref xr = x;


Walter is strongly against adding references a la C++ to D, as he 
believes they are too complicated and bug prone. He's made 
several posts on this, but I can't find them now.
Jan 21 2015
next sibling parent =?UTF-8?B?Ik5vcmRsw7Z3Ig==?= <per.nordlow gmail.com> writes:
On Wednesday, 21 January 2015 at 17:14:29 UTC, Meta wrote:

 Walter is strongly against adding references a la C++ to D, as 
 he believes they are too complicated and bug prone. He's made 
 several posts on this, but I can't find them now.


It would be interesting to read about how Walter thinks here :)

Thanks anyway.
Jan 21 2015
prev sibling next sibling parent "weaselcat" <weaselcat gmail.com> writes:
On Wednesday, 21 January 2015 at 17:14:29 UTC, Meta wrote:

 On Wednesday, 21 January 2015 at 08:23:44 UTC, Per Nordlöw 
 wrote:

 On Wednesday, 21 January 2015 at 08:22:44 UTC, Per Nordlöw 
 wrote:

   int x;
   auto ref xr;


 Correction: I, of course mean,

    int x = 42;
    auto ref xr = x;


 Walter is strongly against adding references a la C++ to D, as 
 he believes they are too complicated and bug prone. He's made 
 several posts on this, but I can't find them now.


Artificial constraints like this and no default constructor 
implementations for structs makes D annoying to use for 
programming that relies heavily on deterministic resource 
management tbh.
Jan 21 2015
prev sibling parent reply "Marc =?UTF-8?B?U2Now7x0eiI=?= <schuetzm gmx.net> writes:
On Wednesday, 21 January 2015 at 17:14:29 UTC, Meta wrote:

 On Wednesday, 21 January 2015 at 08:23:44 UTC, Per Nordlöw 
 wrote:

 On Wednesday, 21 January 2015 at 08:22:44 UTC, Per Nordlöw 
 wrote:

   int x;
   auto ref xr;


 Correction: I, of course mean,

    int x = 42;
    auto ref xr = x;


 Walter is strongly against adding references a la C++ to D, as 
 he believes they are too complicated and bug prone. He's made 
 several posts on this, but I can't find them now.


In DIP69, he himself proposed `ref` locals. However, that's not 
the same as "references a la C++".
Jan 22 2015
parent "Meta" <jared771 gmail.com> writes:
On Thursday, 22 January 2015 at 14:52:26 UTC, Marc Schütz wrote:

 On Wednesday, 21 January 2015 at 17:14:29 UTC, Meta wrote:

 On Wednesday, 21 January 2015 at 08:23:44 UTC, Per Nordlöw 
 wrote:

 On Wednesday, 21 January 2015 at 08:22:44 UTC, Per Nordlöw 
 wrote:

  int x;
  auto ref xr;


 Correction: I, of course mean,

   int x = 42;
   auto ref xr = x;


 Walter is strongly against adding references a la C++ to D, as 
 he believes they are too complicated and bug prone. He's made 
 several posts on this, but I can't find them now.


 In DIP69, he himself proposed `ref` locals. However, that's not 
 the same as "references a la C++".


Hmm, it seems that he did. If D were to allow creating ref 
variables, wouldn't D ref be more or less like in C++, then? 
Aside from the weirder things like T&& and such.
Jan 22 2015