• Eldar Insafutdinov <e.insafutdinov gmail.com> Sep 30 2008
• "Bill Baxter" <wbaxter gmail.com> Sep 30 2008

Eldar Insafutdinov <e.insafutdinov gmail.com> writes:

bearophile Wrote:

 Eldar Insafutdinov:
     auto itCopy = it.clone();






 In D all objects are managed by reference. So when you copy automatically, you
are just copying its reference, that's a pointer fully managed by the GC. If
you want a copy of the data of an object you ask so to it. This simplifies
collections and reduces the number of copies, improving performance.
 
 Instead of "clone()" I suggest "dup", that's the standard in D.
 
 Bye,
 bearophile


Ah ok, so when using "in" with class objects - it means that I can't modify the
reference itself. So no copy occured. I was wrong.

"Bill Baxter" <wbaxter gmail.com> writes:

On Wed, Oct 1, 2008 at 6:01 AM, Eldar Insafutdinov
<e.insafutdinov gmail.com> wrote:
 bearophile Wrote:

 Eldar Insafutdinov:
     auto itCopy = it.clone();






 In D all objects are managed by reference. So when you copy automatically, you
are just copying its reference, that's a pointer fully managed by the GC. If
you want a copy of the data of an object you ask so to it. This simplifies
collections and reduces the number of copies, improving performance.

 Instead of "clone()" I suggest "dup", that's the standard in D.

 Bye,
 bearophile


 Ah ok, so when using "in" with class objects - it means that I can't modify
the reference itself. So no copy occured. I was wrong.


In D1 'in' is a no-op.  It just means pass the parameter normally.
Which for classes means you're actually passing a pointer/reference to
the class.

I've done very little with D2, but in D2 I think 'in' on a parameter
means 'const'.  Or maybe "const final".

--bb