closing files on exit

gistfile1.txt

diff --git a/src/core/IO/Handle.pm b/src/core/IO/Handle.pm
index d76c820..811c0bd 100644
--- a/src/core/IO/Handle.pm
+++ b/src/core/IO/Handle.pm
@@ -19,6 +19,24 @@ my class IO::Handle {
           $!encoding = $encoding || 'utf8')
     }
 
+    # Make sure we close any open files on exit
+    my $opened := nqp::list;
+    END {
+        my int $i = 2;
+        my int $elems = nqp::elems($opened);
+        say "checking 3 .. { $elems - 1}";
+        nqp::while(
+          nqp::islt_i(($i = nqp::add_i($i,1)),$elems),
+          nqp::unless(
+            nqp::isnull(my $PIO := nqp::atpos($opened,$i)),
+nqp::stmts(
+  nqp::say("closing $i"),
+            nqp::closefh($PIO)
+)
+          )
+        )
+    }
+
     method open(IO::Handle:D:
       :$r, :$w, :$x, :$a, :$update,
       :$rw, :$rx, :$ra,
@@ -165,6 +183,7 @@ my class IO::Handle {
                     )
                 ),
             );
+            nqp::bindpos($opened,nqp::filenofh($!PIO),$!PIO);
         }
 
         $!chomp = $chomp;
@@ -205,8 +224,9 @@ my class IO::Handle {
         nqp::if(
           nqp::defined($!PIO),
           nqp::stmts(
+            (my int $fileno = nqp::filenofh($!PIO)),
             nqp::closefh($!PIO), # TODO: catch errors
-            $!PIO := nqp::null
+            nqp::bindpos($opened,$fileno,$!PIO := nqp::null)
           )
         )
     }
@@ -746,10 +766,11 @@ my class IO::Handle {
         # are our $*IN, $*OUT, and $*ERR, and we don't want them closed
         # implicitly via DESTROY, since you can't get them back again.
         nqp::if(
-          nqp::defined($!PIO) && nqp::isgt_i(nqp::filenofh($!PIO), 2),
+          nqp::defined($!PIO)
+            && nqp::isgt_i((my int $fileno = nqp::filenofh($!PIO)), 2),
           nqp::stmts(
             nqp::closefh($!PIO),  # don't bother checking for errors
-            $!PIO := nqp::null
+            nqp::bindpos($opened,$fileno,$!PIO := nqp::null)
           )
         )
     }