From b3d2d0bfcfb1fcff0326436aedc6fe2456df3217 Mon Sep 17 00:00:00 2001
From: Chris Pressey <cpressey@catseye.tc>
Date: Tue, 12 Dec 2017 10:10:58 +0000
Subject: [PATCH] Clearing up a little mystery I had here.

---
 eg/proto-game.60p            |  4 ++++
 tests/SixtyPical Analysis.md | 24 ++++++++++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/eg/proto-game.60p b/eg/proto-game.60p
index c6f0436..56aa5e4 100644
--- a/eg/proto-game.60p
+++ b/eg/proto-game.60p
@@ -123,6 +123,10 @@ routine clear_screen
 // Game States
 // ----------------------------------------------------------------
 
+//
+// Because these all `goto save_cinv` at the end, they must have the same signature as that routine.
+//
+
 routine game_state_play
   inputs joy2, pos
   outputs delta, pos, dispatch_game_state, screen, screen1
diff --git a/tests/SixtyPical Analysis.md b/tests/SixtyPical Analysis.md
index 96c9df4..9b95718 100644
--- a/tests/SixtyPical Analysis.md	
+++ b/tests/SixtyPical Analysis.md	
@@ -1513,6 +1513,30 @@ But not if the vector is declared inappropriately.
     | }
     ? IncompatibleConstraintsError
 
+"Appropriately" means, if the routine affects no more than what is named
+in the input/output sets of the vector.
+
+    | vector vec
+    |   inputs a, x
+    |   outputs x
+    |   trashes a, z, n
+    | 
+    | routine foo
+    |   inputs x
+    |   outputs x
+    |   trashes z, n
+    | {
+    |   inc x
+    | }
+    | 
+    | routine main
+    |   outputs vec
+    |   trashes a, z, n
+    | {
+    |     copy foo, vec
+    | }
+    = ok
+
 Routines are read-only.
 
     | vector vec