From a005e678dbc9fbccc1acac234eaf0aa83bbecad8 Mon Sep 17 00:00:00 2001
From: Slava Pestov <slava@slava-pestovs-macbook-pro.local>
Date: Mon, 1 Feb 2010 20:54:08 +1300
Subject: [PATCH] classes.tuple: make error slots read only for small space
 savings

---
 core/classes/tuple/tuple.factor | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/core/classes/tuple/tuple.factor b/core/classes/tuple/tuple.factor
index e3b5126713..ee49980f4d 100644
--- a/core/classes/tuple/tuple.factor
+++ b/core/classes/tuple/tuple.factor
@@ -250,6 +250,13 @@ GENERIC# (define-tuple-class) 2 ( class superclass slots -- )
 : thrower-effect ( slots -- effect )
     [ name>> ] map { "*" } <effect> ;
 
+: error-slots ( slots -- slots' )
+    [
+        dup string? [ 1array ] when
+        read-only swap remove
+        read-only suffix
+    ] map ;
+
 PRIVATE>
 
 : define-tuple-class ( class superclass slots -- )
@@ -265,6 +272,7 @@ M: tuple-class (define-tuple-class)
     [ 2drop ?define-symbol ] [ redefine-tuple-class ] if ;
 
 : define-error-class ( class superclass slots -- )
+    error-slots
     [ define-tuple-class ]
     [ 2drop reset-generic ]
     [