Global initialization checks name conflict

Initialization "global a = 10" raises an error if global 'a' is already
defined, that is, it has a non-nil value.

1 files changed, 2 insertions, 0 deletions

diff --git a/lopcodes.h b/lopcodes.h
index 82bba721..f7bded2c 100644
--- a/lopcodes.h
+++ b/lopcodes.h
@@ -340,6 +340,8 @@ OP_VARARG,/*	A C	R[A], R[A+1], ..., R[A+C-2] = vararg		*/
 
 OP_GETVARG, /* A B C    R[A] := R[B][R[C]], R[B] is vararg parameter    */
 
+OP_ERRNNIL,/*   A Bx    raise error if R[A] ~= nil (K[Bx] is global name)*/
+
 OP_VARARGPREP,/*        (adjust vararg parameters)                      */
 
 OP_EXTRAARG/*   Ax      extra (larger) argument for previous opcode     */