• d-bugmail puremagic.com (47/47) May 25 2008 http://d.puremagic.com/issues/show_bug.cgi?id=2131

d-bugmail puremagic.com writes:

http://d.puremagic.com/issues/show_bug.cgi?id=2131

           Summary: Template scope access
           Product: D
           Version: 2.014
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: enhancement
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: simen.kjaras gmail.com


In my post "Template alias parameter mixin import inference" (
http://www.digitalmars.com/webnews/newsgroups.php?art_group=digitalmars.D&article_id=68798
), and in bug 2125 ( http://d.puremagic.com/issues/show_bug.cgi?id=2125,
"Moving a template to a separate module breaks compilation" ), it is
demonstrated that giving a template access to both its declaration scope and
its instantiation scope might give more logical and desireable behavior.

Example code:

//////////////////////

module a;
import std.stdio;

template bar()
{
        int i;

        void func()
        {
                writefln(i);
        }
}

void main()
{
        foo!(bar) a;
        a.func();
}

//////////////////////

module b;

struct foo(alias T)
{
        mixin T!();
}

//////////////////////

Gives error message "b.d(5): Error: undefined identifier writefln".

Currently, this can be fixed by placing import statements within the template
declaration, but allowing access to more scopes would make it easier for the
programmer.


--