scoped chdir and similar patterns

[qznc]

On Thursday, 5 December 2013 at 01:07:19 UTC, Timothee Cour wrote:
> A1.
>
> Is there a (clever?) way to achieve the following using a 
> single function
> call?

You could (mis)use destructors.

=============
struct chdir_scoped {
   string olddir;
   this(string newdir) {
     olddir = "bar";
     writeln("chdir to "~newdir);
   }
   ~this() {
     writeln("chdir back to "~olddir);
   }
}

int main() {
   auto x = chdir_scoped("foo");
   writeln("doing work in foo");
   return 0;
}
=============
Output:
chdir to foo
doing work in foo
chdir back to bar
=============

Feels hacky to me, since "x" is not used anywhere.