From 5debe86536f66ddb74bc5d49aa17ef550d772ca4 Mon Sep 17 00:00:00 2001
From: Matthew Fioravante <fmatthew5876@gmail.com>
Date: Sat, 13 Apr 2019 11:39:44 -0400
Subject: [PATCH] Add ReserveSubcommandIndex()

---
 src/game_interpreter.cpp | 9 ++++++---
 src/game_interpreter.h   | 1 +
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/game_interpreter.cpp b/src/game_interpreter.cpp
index 9114d3caf16..e11420c9d7b 100644
--- a/src/game_interpreter.cpp
+++ b/src/game_interpreter.cpp
@@ -262,8 +262,7 @@ int Game_Interpreter::GetThisEventId() const {
 	return event_id;
 }
 
-
-void Game_Interpreter::SetSubcommandIndex(int indent, int idx) {
+uint8_t& Game_Interpreter::ReserveSubcommandIndex(int indent) {
 	auto* frame = GetFrame();
 	assert(frame);
 
@@ -273,7 +272,11 @@ void Game_Interpreter::SetSubcommandIndex(int indent, int idx) {
 		// the array with uninitialized values.
 		path.resize(indent + 1, subcommand_sentinel);
 	}
-	path[indent] = idx;
+	return path[indent];
+}
+
+void Game_Interpreter::SetSubcommandIndex(int indent, int idx) {
+	ReserveSubcommandIndex(indent) = idx;
 }
 
 int Game_Interpreter::GetSubcommandIndex(int indent) const {
diff --git a/src/game_interpreter.h b/src/game_interpreter.h
index 2377e27459d..cddb66df7db 100644
--- a/src/game_interpreter.h
+++ b/src/game_interpreter.h
@@ -255,6 +255,7 @@ class Game_Interpreter
 	void OnChangeSystemGraphicReady(FileRequestResult* result);
 
 	void SetSubcommandIndex(int indent, int idx);
+	uint8_t& ReserveSubcommandIndex(int indent);
 	int GetSubcommandIndex(int indent) const;
 
 	FileRequestBinding request_id;