--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ChangeDeltaInformation.st	Wed Aug 31 11:45:27 2011 +0200
@@ -0,0 +1,135 @@
+"{ Package: 'stx:libbasic3' }"
+
+Object subclass:#ChangeDeltaInformation
+	instanceVariableNames:'shortDeltaSymbol'
+	classVariableNames:'Unknown Identical Different Added Removed IdenticalButWhiteSpace
+		IdenticalButFormat IdenticalSemantically'
+	poolDictionaries:''
+	category:'System-Changes'
+!
+
+!ChangeDeltaInformation class methodsFor:'documentation'!
+
+documentation
+"
+    delta used to return a symbol (#=, #~, #+ or #-);
+    for more detail, use instances of me:
+        Unknown                 delta is unknown
+        Identical               exactly the same
+        IdenticalButWhiteSpace  code is formatted different, but AST is the same
+        SemanticallyIdentical   code is different, but semantically the same
+                                (for example, ifNil: -> isNil ifTrue:)
+        Different               code is different
+        Added                   method/class is added by change
+        Removed                 method/class is removed by change
+"
+! !
+
+!ChangeDeltaInformation class methodsFor:'initialization'!
+
+initialize
+    Unknown                 := self new shortDeltaSymbol:#'?'.    "/ delta is unknown
+    Identical               := self new shortDeltaSymbol:#'='.    "/ exactly the same
+    IdenticalButWhiteSpace  := self new shortDeltaSymbol:#'W'.    "/ code is the same except for indentation
+    IdenticalButFormat      := self new shortDeltaSymbol:#'F'.    "/ code is formatted different, but AST is the same
+    IdenticalSemantically   := self new shortDeltaSymbol:#'%'.    "/ code is different, but semantically the same
+                                                                  "/ (for example, ifNil: -> isNil ifTrue:)
+    Different               := self new shortDeltaSymbol:#'~'.    "/ code is different
+    Added                   := self new shortDeltaSymbol:#'+'.    "/ method/class is added by change
+    Removed                 := self new shortDeltaSymbol:#'-'.    "/ method/class is removed by change
+
+    "Created: / 31-08-2011 / 10:09:24 / cg"
+! !
+
+!ChangeDeltaInformation class methodsFor:'accessing'!
+
+added
+    "method/class is added by change"
+
+    ^ Added
+
+    "Modified (comment): / 31-08-2011 / 10:20:51 / cg"
+!
+
+different
+    "code is different"
+
+    ^ Different
+
+    "Modified (comment): / 31-08-2011 / 10:21:07 / cg"
+!
+
+identical
+    "exactly the same"
+
+    ^ Identical
+
+    "Modified (comment): / 31-08-2011 / 10:21:18 / cg"
+!
+
+identicalButFormat
+    "code is formatted different, but AST is the same"
+
+    ^ IdenticalButFormat
+
+    "Created: / 31-08-2011 / 10:23:18 / cg"
+!
+
+identicalButWhiteSpace
+    "code is the same except for indentation"
+
+    ^ IdenticalButWhiteSpace
+
+    "Modified (comment): / 31-08-2011 / 10:23:49 / cg"
+!
+
+identicalSemantically
+    "code is different, but semantically the same.
+     (for example, ifNil: -> isNil ifTrue:)"
+
+    ^ IdenticalSemantically
+
+    "Modified (comment): / 31-08-2011 / 10:24:04 / cg"
+!
+
+removed
+    "method/class is removed by change"
+
+    ^ Removed
+
+    "Modified (comment): / 31-08-2011 / 10:24:14 / cg"
+!
+
+unknown
+    "another change / cannot figure out what has changed"
+
+    ^ Unknown
+
+    "Created: / 31-08-2011 / 10:20:13 / cg"
+! !
+
+!ChangeDeltaInformation methodsFor:'accessing'!
+
+shortDeltaSymbol
+    ^ shortDeltaSymbol
+
+    "Created: / 31-08-2011 / 10:39:01 / cg"
+!
+
+shortDeltaSymbol:something
+    shortDeltaSymbol := something.
+
+    "Created: / 31-08-2011 / 10:39:05 / cg"
+! !
+
+!ChangeDeltaInformation class methodsFor:'documentation'!
+
+version
+    ^ '$Header: /cvs/stx/stx/libbasic3/ChangeDeltaInformation.st,v 1.1 2011-08-31 09:45:27 cg Exp $'
+!
+
+version_CVS
+    ^ '$Header: /cvs/stx/stx/libbasic3/ChangeDeltaInformation.st,v 1.1 2011-08-31 09:45:27 cg Exp $'
+! !
+
+ChangeDeltaInformation initialize!