--- a/compiler/TUnionType.st	Tue Aug 25 19:05:18 2015 +0100
+++ b/compiler/TUnionType.st	Wed Aug 26 07:51:18 2015 +0100
@@ -15,6 +15,12 @@
     ^ self new initializeWith: type1 and: type2
 
     "Created: / 21-08-2015 / 18:38:21 / Jan Vrany <jan.vrany@fit.cvut.cz>"
+!
+
+withAll: types
+    ^ self new initializeWithAll: types
+
+    "Created: / 25-08-2015 / 22:51:01 / Jan Vrany <jan.vrany@fit.cvut.cz>"
 ! !
 
 !TUnionType methodsFor:'accessing'!
@@ -23,6 +29,18 @@
     ^ types
 ! !
 
+!TUnionType methodsFor:'comparing'!
+
+hash
+    | h |
+
+    h := types size.
+    types do:[:type | h := h bitXor: type hash ].
+    ^ h
+
+    "Created: / 25-08-2015 / 23:35:28 / Jan Vrany <jan.vrany@fit.cvut.cz>"
+! !
+
 !TUnionType methodsFor:'initialization'!
 
 initializeWith: type1 with: type2
@@ -34,6 +52,18 @@
         ifFalse:[ types := types copyWith: type2 ].
 
     "Created: / 21-08-2015 / 18:39:44 / Jan Vrany <jan.vrany@fit.cvut.cz>"
+!
+
+initializeWithAll: aCollection
+    types := OrderedCollection new: aCollection size.
+    aCollection do:[:type | 
+        type isUnionType 
+            ifTrue:[ types addAll: type types ]
+            ifFalse:[types add: type ].
+    ].
+    types := types asArray.
+
+    "Created: / 25-08-2015 / 22:50:48 / Jan Vrany <jan.vrany@fit.cvut.cz>"
 ! !
 
 !TUnionType methodsFor:'testing'!