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digitalmars.D.bugs - [Issue 4832] New: Functions external to class break immutability

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=4832

           Summary: Functions external to class break immutability
           Product: D
           Version: D2
          Platform: Other
        OS/Version: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: andrej.mitrovich gmail.com



13:37:14 PDT ---
Code:

import std.stdio : writeln;

void foo(ref int x)
{
    x = 10;
}

class Bar
{
    immutable int x;

    this()
    {
        x = 5;
    }

    void printMe()
    {
        writeln(this.x);
    }

    void change()
    {
        //~ this.x = 20;    // illegal, errors out
    }
}

void main()
{
    Bar bar = new Bar;
    bar.printMe();  // prints 5

    //~ bar.x = 10;  // illegal, errors out

    foo(bar.x);     // no error!
    bar.printMe();  // prints 10
}

The commented out code would error out at compile time, which is expected. But
the function bar() is breaking immutability of x.

A relevant bug is bug 4416 , and my comment:
http://d.puremagic.com/issues/show_bug.cgi?id=4416#c1

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next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=4832




13:37:55 PDT ---
Sorry, I meant the function foo, not bar.



 Code:
 
 import std.stdio : writeln;
 
 void foo(ref int x)
 {
     x = 10;
 }
 
 class Bar
 {
     immutable int x;
 
     this()
     {
         x = 5;
     }
 
     void printMe()
     {
         writeln(this.x);
     }
 
     void change()
     {
         //~ this.x = 20;    // illegal, errors out
     }
 }
 
 void main()
 {
     Bar bar = new Bar;
     bar.printMe();  // prints 5
 
     //~ bar.x = 10;  // illegal, errors out
 
     foo(bar.x);     // no error!
     bar.printMe();  // prints 10
 }
 
 The commented out code would error out at compile time, which is expected. But
 the function bar() is breaking immutability of x.
 
 A relevant bug is bug 4416 , and my comment:
 http://d.puremagic.com/issues/show_bug.cgi?id=4416#c1


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prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=4832


yebblies <yebblies gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |yebblies gmail.com
         Resolution|                            |DUPLICATE



*** This issue has been marked as a duplicate of issue 5493 ***

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