Make state $zok = slosh(); behave as the Perl 6 design with an implicit

START block. First time through, call slosh() and assign to $zok.
Subsequently neither call slosh() nor assign to $zok. Adds a new op
ONCE to control the conditonal call and assign. No change to list
context, so state ($zok) = slosh() and (state $zok) = ... etc will
still repeatedly evaluate and assign. [Can't fix that before 5.10]
Use as an RVALUE is as Larry's design - my $boff = state $zok = ...;
will evaluate, assign and return first time, and subsequently act as if
it were written my $boff = $zok;
FIXME - state $zok = ...; won't deparse - I believe op->op_last isn't
being correctly set on the sassign, but I don't know how to fix this.
This change may be backed out before 5.10.

p4raw-id: //depot/perl@31798

1 files changed, 1 insertions, 0 deletions

diff --git a/pp.sym b/pp.sym
index 8e1495f296..f5136ea252 100644
--- a/pp.sym
+++ b/pp.sym
@@ -404,5 +404,6 @@ Perl_pp_egrent
 Perl_pp_getlogin
 Perl_pp_syscall
 Perl_pp_lock
+Perl_pp_once
 
 # ex: set ro: