Perl DESTROY Scoping Semantics

00-noprint-after-undef.pl

local *Foo::c = sub { print "IN MY C\n" };
my $f = Foo->new();
Foo::c();
Foo::d();
e();
undef $f;

__END__

Output
------
IN MY C
IN MY C
IN MY C
IN DESTROY
IN ORIG C  <===

01-print-after-undef.pl

local *Foo::c = sub { print "IN MY C\n" };
my $f = Foo->new();
Foo::c();
Foo::d();
e();
undef $f;
print "DONE\n";

__END__

Output
------
IN MY C
IN MY C
IN MY C
IN DESTROY
IN MY C  <===
DONE

02-noprint-concise.out

j  <@> leave[1 ref] vKP/REFC ->(end)
1     <0> enter ->2
2     <;> nextstate(main 11 local_destroy.pl:26) v:*,&,{,x*,x&,x$,$ ->3
-     <0> ex-const v ->-
-     <0> null v ->3
8     <2> sassign vKS/2 ->9
5        <1> refgen sK/1 ->6
-           <1> ex-list lKRM ->5
3              <0> pushmark sRM ->4
4              <$> anoncode[CV ] lRM ->5
7        <1> rv2gv sKRM*/LVINTRO,3 ->8
6           <$> gv(*Foo::c) s ->7
9     <;> nextstate(main 11 local_destroy.pl:27) v:*,&,{,x*,x&,x$,$ ->a
f     <2> sassign vKS/2 ->g
d        <1> entersub[t3] sKS/TARG,2 ->e
a           <0> pushmark s ->b
b           <$> const(PV "Foo") sM/BARE ->c
c           <$> method_named(PV "new") s ->d
e        <0> padsv[$f:11,12] sRM*/LVINTRO ->f
g     <;> nextstate(main 12 local_destroy.pl:28) v:*,&,{,x*,x&,x$,$ ->h
i     <1> undef vK/1 ->j
h        <0> padsv[$f:11,12] sRM ->i

03-print-concise.out

n  <@> leave[1 ref] vKP/REFC ->(end)
1     <0> enter ->2
2     <;> nextstate(main 11 local_destroy.pl:26) v:*,&,{,x*,x&,x$,$ ->3
-     <0> ex-const v ->-
-     <0> null v ->3
8     <2> sassign vKS/2 ->9
5        <1> refgen sK/1 ->6
-           <1> ex-list lKRM ->5
3              <0> pushmark sRM ->4
4              <$> anoncode[CV ] lRM ->5
7        <1> rv2gv sKRM*/LVINTRO,3 ->8
6           <$> gv(*Foo::c) s ->7
9     <;> nextstate(main 11 local_destroy.pl:27) v:*,&,{,x*,x&,x$,$ ->a
f     <2> sassign vKS/2 ->g
d        <1> entersub[t3] sKS/TARG,2 ->e
a           <0> pushmark s ->b
b           <$> const(PV "Foo") sM/BARE ->c
c           <$> method_named(PV "new") s ->d
e        <0> padsv[$f:11,12] sRM*/LVINTRO ->f
g     <;> nextstate(main 12 local_destroy.pl:28) v:*,&,{,x*,x&,x$,$ ->h
i     <1> undef vK/1 ->j
h        <0> padsv[$f:11,12] sRM ->i
j     <;> nextstate(main 12 local_destroy.pl:29) v:*,&,{,x*,x&,x$,$ ->k
m     <@> print vK ->n
k        <0> pushmark s ->l
l        <$> const(PV "DONE") s ->m

04-diff-concise.out

[✔]▶ diff /tmp/noprint.out /tmp/print.out
--- /tmp/noprint.out    2015-03-22 18:23:12.308776994 -0500
+++ /tmp/print.out      2015-03-22 18:23:21.522110342 -0500
@@ -1,4 +1,4 @@
-j  <@> leave[1 ref] vKP/REFC ->(end)
+n  <@> leave[1 ref] vKP/REFC ->(end)
 1     <0> enter ->2
 2     <;> nextstate(main 11 local_destroy.pl:26) v:*,&,{,x*,x&,x$,$ ->3
 -     <0> ex-const v ->-
@@ -20,3 +20,7 @@
 g     <;> nextstate(main 12 local_destroy.pl:28) v:*,&,{,x*,x&,x$,$ ->h
 i     <1> undef vK/1 ->j
 h        <0> padsv[$f:11,12] sRM ->i
+j     <;> nextstate(main 12 local_destroy.pl:29) v:*,&,{,x*,x&,x$,$ ->k
+m     <@> print vK ->n
+k        <0> pushmark s ->l
+l        <$> const(PV "DONE") s ->m