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digitalmars.D.learn - symbolless stack allocation

reply "Jay" <jaypinkman hotmail.com> writes:
as specified here: 
http://wiki.dlang.org/Memory_Management#Allocating_Class_Instances_On_The_Stack

i can allocate a class instance on the stack (inside a funtion) 
like so:

scope c = new C();

i want to create an instance, call one of its methods, and throw 
it away. like so:

scope new C().doSomething();

can i somehow do away with declaring a local variable and calling 
a method on it?
Sep 10 2014
parent reply =?UTF-8?B?QWxpIMOHZWhyZWxp?= <acehreli yahoo.com> writes:
On 09/10/2014 11:31 AM, Jay wrote:


 as specified here:
 


http://wiki.dlang.org/Memory_Management#Allocating_Class_Instances_On_The_Stack 


 i can allocate a class instance on the stack (inside a funtion) like so:

 scope c = new C();


That usage of 'scope' is deprecated. There is std.typecons.scoped instead.


 i want to create an instance, call one of its methods, and throw it
 away. like so:

 scope new C().doSomething();

 can i somehow do away with declaring a local variable and calling a
 method on it?


Yes.

import std.stdio;
import std.typecons;

class C
{
     int i;

     this (int i)
     {
         this.i = i;
     }

     void foo()
     {
         writeln(i);
     }
}

void main()
{
     scoped!C(42).foo();
}

Ali
Sep 10 2014
parent "Jay" <jaypinkman hotmail.com> writes:
On Wednesday, 10 September 2014 at 19:39:17 UTC, Ali Çehreli 
wrote:


 scope c = new C();


 That usage of 'scope' is deprecated. There is 
 std.typecons.scoped instead.


actually i read about 'scoped' here 
http://ddili.org/ders/d.en/destroy.html (thanks for the tutorial 
btw) but i thought that 'scoped() wraps the class object inside a 
struct' means that the struct contains a reference to a heap 
allocated object. i guess i should've looked up the documentation 
for 'scoped'. thanks.
Sep 10 2014