• thanate <nospam spam.com> Oct 30 2010
• Jonathan M Davis <jmdavisProg gmx.com> Oct 30 2010
• thanate <nospam spam.com> Oct 30 2010
• bearophile <bearophileHUGS lycos.com> Oct 30 2010

thanate <nospam spam.com> writes:

Hi,

dmd v2.050 give the following error:

hello.d(10): Error: undefined identifier module hello.dup

for the following code (hello.d):
---------------------
import std.stdio;
import std.array;
import std.string;

void main()
{
  uint[string] s;
  s["a"]=1;
  s["b"]=2;
  uint[string] r = s.dup;
  r["b"]=3;
  writeln(r["b"]," ",s["b"]);
}
---------------------

Could anyone explain why should this be an error?

Thanks!
thanate

Jonathan M Davis <jmdavisProg gmx.com> writes:

On Saturday 30 October 2010 12:12:48 thanate wrote:
 Hi,
 
 dmd v2.050 give the following error:
 
 hello.d(10): Error: undefined identifier module hello.dup
 
 for the following code (hello.d):
 ---------------------
 import std.stdio;
 import std.array;
 import std.string;
 
 void main()
 {
   uint[string] s;
   s["a"]=1;
   s["b"]=2;
   uint[string] r = s.dup;
   r["b"]=3;
   writeln(r["b"]," ",s["b"]);
 }
 ---------------------
 
 Could anyone explain why should this be an error?
 
 Thanks!
 thanate


Easy. s is an associate array, not an array, and for whatever reason, 
associative arrays don't have a dup property: 
http://www.digitalmars.com/d/2.0/hash-map.html

I believe that if you want a deep copy, you're going to have to create a new
one 
and then copy all of the elements over in a loop.

- Jonathan M Davis

thanate <nospam spam.com> writes:

This does seem like a strange omission. But thanks for the answer!

thanate

bearophile <bearophileHUGS lycos.com> writes:

thanate:

 This does seem like a strange omission. But thanks for the answer!


Indeed, some methods are missing in the built-in associative arrays. I think
Andrei likes the idea of adding few more methods (dup too) to those AAs, but no
one has found the time to implement them yet.

Bye,
bearophile