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, 3 insertions, 2 deletions

diff --git a/opnames.h b/opnames.h
index e09cb084d2..d2633e6bc5 100644
--- a/opnames.h
+++ b/opnames.h
@@ -375,11 +375,12 @@ typedef enum opcode {
 	OP_GETLOGIN,	/* 357 */
 	OP_SYSCALL,	/* 358 */
 	OP_LOCK,	/* 359 */
-	OP_CUSTOM,	/* 360 */
+	OP_ONCE,	/* 360 */
+	OP_CUSTOM,	/* 361 */
 	OP_max		
 } opcode;
 
-#define MAXO 361
+#define MAXO 362
 #define OP_phoney_INPUT_ONLY -1
 #define OP_phoney_OUTPUT_ONLY -2