--- a/Interval.st	Wed Oct 31 15:57:14 2001 +0100
+++ b/Interval.st	Wed Oct 31 15:57:48 2001 +0100
@@ -12,7 +12,7 @@
 
 "{ Package: 'stx:libbasic' }"
 
-SequenceableCollection subclass:#Interval
+ReadOnlySequenceableCollection subclass:#Interval
 	instanceVariableNames:'start stop step'
 	classVariableNames:''
 	poolDictionaries:''
@@ -87,7 +87,8 @@
      Re-redefined, since the implementation in SeqColl creates instances with an initial
      size, which is not allowed for intevals."
 
-    ^ self new fromLiteralArrayEncoding:anArray.! !
+    ^ self new fromLiteralArrayEncoding:anArray.
+! !
 
 !Interval methodsFor:'accessing'!
 
@@ -100,14 +101,6 @@
     ^ self subscriptBoundsError:index
 !
 
-at:index put:anObject
-    "{ Pragma: +optSpace }"
-
-    "catch at:put: message - intervals cannot store elements"
-
-    self error:'you cannot store into an interval'
-!
-
 first
     "return the first element of the collection"
 
@@ -172,24 +165,6 @@
     stop := aNumber
 ! !
 
-!Interval methodsFor:'adding & removing'!
-
-add:newObject
-    "{ Pragma: +optSpace }"
-
-    "catch add message - intervals cannot add elements"
-
-    self error:'elements cannot be added to an interval'
-!
-
-remove:anObject
-    "{ Pragma: +optSpace }"
-
-    "catch remove message - intervals cannot remove elements"
-
-    self error:'elements cannot be removed from an interval'
-! !
-
 !Interval methodsFor:'converting'!
 
 fromLiteralArrayEncoding:encoding
@@ -206,7 +181,8 @@
      Interval new fromLiteralArrayEncoding:((1 to:10) literalArrayEncoding)  
      Interval new fromLiteralArrayEncoding:((1 to:10 by:2) literalArrayEncoding) 
      Interval decodeFromLiteralArray:((1 to:10 by:2) literalArrayEncoding) 
-    "!
+    "
+!
 
 literalArrayEncoding
     "encode myself as an array literal, from which a copy of the receiver
@@ -221,7 +197,8 @@
     "
      (1 to:10) literalArrayEncoding      
      (1 to:10 by:2) literalArrayEncoding
-    "! !
+    "
+! !
 
 !Interval methodsFor:'enumerating'!
 
@@ -378,5 +355,5 @@
 !Interval class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/Interval.st,v 1.28 2000-10-24 14:31:26 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/Interval.st,v 1.29 2001-10-31 14:57:48 cg Exp $'
 ! !