Unset local for variable, fixes #62

engine/vm.c

@@ -2292,6 +2292,28 @@ static sxi32 VmByteCodeExec(
 					}
 					break;
 				}
+			/*
+			 * UNSET: * * P3
+			 *
+			 * Unset a variable. It takes the variable name indexed at P3 operand.
+			 */
+			case PH7_OP_UNSET: {
+				SyString sName;
+				VmFrame *pFrame = pVm->pFrame;
+				SyHashEntry *pEntry;
+				sxu32 nIdx;
+				SyStringInitFromBuf(&sName, pInstr->p3, SyStrlen((const char *)pInstr->p3));
+				/* Find variable in local frame */
+				pEntry = SyHashGet(&pFrame->hVar, (const void *)sName.zString, sName.nByte);
+				if(pEntry) {
+					nIdx = (sxu32)SX_PTR_TO_INT(pEntry->pUserData);
+					/* Delete variable from local frame */
+					SyHashDeleteEntry(&pFrame->hVar, (const void *)sName.zString, sName.nByte, 0);
+					/* Call PH7_VmUnsetMemObj to release the variable */
+					PH7_VmUnsetMemObj(&(*pVm), nIdx, FALSE);
+				}
+				break;
+			}
 			/*
 			 * LOADC P1 P2 *
 			 *