diff --git a/src/SmallSuiteGenerator-Tests/SChangeTest.class.st b/src/SmallSuiteGenerator-Tests/SChangeTest.class.st
index 8181fad..a6a01a3 100644
--- a/src/SmallSuiteGenerator-Tests/SChangeTest.class.st
+++ b/src/SmallSuiteGenerator-Tests/SChangeTest.class.st
@@ -16,12 +16,12 @@ SChangeTest >> testChangeStatementOfFactoryMessageWithAbstractClass [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := ArrayedCollection new.' '_var1 := ''hello''.' '_var2 := ArrayedCollection new.').
+			#('_anArrayedCollection0 := ArrayedCollection new.' '_aByteString1 := ''hello''.' '_anArrayedCollection2 := ArrayedCollection new.').
 	changed := testCase changeStatementOfClassName: #ArrayedCollection.
 	self assert: changed equals: false.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var1 := ''hello''.')
+		hasSameElements: #('_aByteString1 := ''hello''.')
 ]
 
 { #category : #'mutation-change' }
@@ -34,15 +34,15 @@ SChangeTest >> testChangeStatementOfFactoryMessageWithMoreThanOneLiteral [
 	expression := testCase addFactoryMessage: #SFoo ofSelector: #score:.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		includesAll: #('_var0 := 7.3.' '_var1 := 7.3.').
+		includesAll: #('_aSmallFloat640 := 7.3.' '_aSmallFloat641 := 7.3.').
 	self
 		assert:
-			(#('_var2 := SFoo score: _var0.' '_var2 := SFoo score: _var1.')
+			(#('_aSFoo2 := SFoo score: _aSmallFloat640.' '_aSFoo2 := SFoo score: _aSmallFloat641.')
 				includes: expression printString).
-	expressionChanged := testCase changeStatementOfVarName: '_var2'.
+	expressionChanged := testCase changeStatementOfVarName: '_aSFoo2'.
 	self
 		assert:
-			(#('_var2 := SFoo score: _var0.' '_var2 := SFoo score: _var1.' '_var2 := SFoo new.')
+			(#('_aSFoo2 := SFoo score: _aSmallFloat640.' '_aSFoo2 := SFoo score: _aSmallFloat641.' '_aSFoo2 := SFoo new.')
 				includes: expressionChanged printString).
 	self assert: testCase validReferences
 ]
@@ -55,11 +55,11 @@ SChangeTest >> testChangeStatementOfFactoryMessageWithOneLiteral [
 	addFactoryMessage.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.').
-	expressionChanged := testCase changeStatementOfVarName: '_var1'.
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.').
+	expressionChanged := testCase changeStatementOfVarName: '_aSFoo1'.
 	self
 		assert:
-			(#('_var1 := SFoo new.' '_var1 := SFoo score: _var2.')
+			(#('_aSFoo1 := SFoo new.' '_aSFoo1 := SFoo score: _aSmallFloat642.')
 				includes: expressionChanged printString).
 	self assert: testCase validReferences
 ]
@@ -75,11 +75,11 @@ SChangeTest >> testChangeStatementOfFieldAccessMessage [
 		from: #SStack) copy.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := SStack newStack.' '_var1 := _var0 firstLinkStack.').
+		hasSameElements: #('_aSStack0 := SStack newStack.' '_aSmallInteger1 := _aSStack0 firstLinkStack.').
 	exprFieldChanged := testCase changeStatement: exprField.
 	self
 		assert:
-			(#('_var1 := _var0 lastLinkStack.' '_var1 := _var3 firstLinkStack.' '_var1 := _var2 firstLinkStack.')
+			(#('_aSmallInteger1 := _aSStack0 lastLinkStack.' '_aSmallInteger1 := _aSStack3 firstLinkStack.' '_aSmallInteger1 := _aSStack2 firstLinkStack.')
 				includes: exprFieldChanged printString).
 	self assert: testCase validReferences
 ]
@@ -91,8 +91,8 @@ SChangeTest >> testChangeStatementOfLiteral [
 	exprLiteral := (testCase addLiteral: #SmallInteger) copy.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 5.').
-	exprLiteralChanged := testCase changeStatementOfVarName: '_var0'.
+		hasSameElements: #('_aSmallInteger0 := 5.').
+	exprLiteralChanged := testCase changeStatementOfVarName: '_aSmallInteger0'.
 	self deny: exprLiteral equals: exprLiteralChanged.
 	self assert: testCase validReferences
 ]
@@ -106,11 +106,11 @@ SChangeTest >> testChangeStatementOfMessage [
 	exprMessage := (testCase addMessage: #pop from: #SStack) copy.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := SStack newStack.' '_var1 := _var0 pop.').
+		hasSameElements: #('_aSStack0 := SStack newStack.' '_aSmallInteger1 := _aSStack0 pop.').
 	exprLiteralChanged := testCase changeStatement: exprMessage.
 	self
 		assert:
-			(#('_var1 := _var0 top.' '_var1 := _var0 push: _var2.' '_var1 := _var3 pop.' '_var1 := _var2 pop.')
+			(#('_aSmallInteger1 := _aSStack0 top.' '_aSmallInteger1 := _aSStack0 push: _aSmallInteger2.' '_aSmallInteger1 := _aSStack3 pop.' '_aSmallInteger1 := _aSStack2 pop.')
 				includes: exprLiteralChanged printString).
 	self assert: testCase validReferences
 ]
diff --git a/src/SmallSuiteGenerator-Tests/SFactoryMessageTest.class.st b/src/SmallSuiteGenerator-Tests/SFactoryMessageTest.class.st
index 77a484d..f2d81db 100644
--- a/src/SmallSuiteGenerator-Tests/SFactoryMessageTest.class.st
+++ b/src/SmallSuiteGenerator-Tests/SFactoryMessageTest.class.st
@@ -33,13 +33,13 @@ SFactoryMessageTest >> testInsertAsParameterUsing [
 	testCase addMessage.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := SFoo new.' '_var1 := _var0 return: _var0.').
+		hasSameElements: #('_aSFoo0 := SFoo new.' '_aSFoo1 := _aSFoo0 return: _aSFoo0.').
 	insertedExpression := expression
 		insertAsParameter: expression
 		using: testCase.
 	self
 		assert:
-			(#('_var1 := _var0 return: _var0.')
+			(#('_aSFoo1 := _aSFoo0 return: _aSFoo0.')
 				includes: insertedExpression printString)
 ]
 
@@ -51,7 +51,7 @@ SFactoryMessageTest >> testInsertMethodMessageUsing [
 	expression := testCase addFactoryMessage: #SFoo.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.').
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.').
 	self
 		should: [ expression insertMethodMessage: expression using: testCase ]
 		raise: SError
@@ -65,10 +65,10 @@ SFactoryMessageTest >> testInsertRandomMessageUsing [
 	factoryMessage := testCase addFactoryMessage: #SFoo.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.').
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.').
 	factoryMessage insertRandomMessage: factoryMessage using: testCase.
 	self
 		assertCollection: (testCase statements collect: #printString)
 		includesAll:
-			#('_var0 := 7.3.' '_var2 := SFoo score: _var0.' '_var1 := SFoo score: _var0.')
+			#('_aSmallFloat640 := 7.3.' '_aSFoo2 := SFoo score: _aSmallFloat640.' '_aSFoo1 := SFoo score: _aSmallFloat640.')
 ]
diff --git a/src/SmallSuiteGenerator-Tests/SFieldAccessMessageTest.class.st b/src/SmallSuiteGenerator-Tests/SFieldAccessMessageTest.class.st
index 02b41bf..860f267 100644
--- a/src/SmallSuiteGenerator-Tests/SFieldAccessMessageTest.class.st
+++ b/src/SmallSuiteGenerator-Tests/SFieldAccessMessageTest.class.st
@@ -13,14 +13,14 @@ SFieldAccessMessageTest >> testCopy [
 				id: 0;
 				returnType: #SStack);
 		selector: #firstLinkStack.
-	self assert: expression printString equals: '_var0 firstLinkStack'.
+	self assert: expression printString equals: '_aSStack0 firstLinkStack'.
 	copy := expression copy.
 	copy value receiver varName: '_sstack'.
 	copy value receiver id: 4.
 	self assert: copy printString equals: '_sstack4 firstLinkStack'.
 	copy value selector: #lastLinkStack.
 	self assert: copy printString equals: '_sstack4 lastLinkStack'.
-	self assert: expression printString equals: '_var0 firstLinkStack'
+	self assert: expression printString equals: '_aSStack0 firstLinkStack'
 ]
 
 { #category : #tests }
@@ -35,14 +35,14 @@ SFieldAccessMessageTest >> testInsertAsParameterUsing [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := #(1 4 5 ).' '_var1 := SStack newStackWith: _var0.' '_var2 := _var1 firstLinkStack.' '_var3 := 5.').
+			#('_anArray0 := #(1 4 5 ).' '_aSStack1 := SStack newStackWith: _anArray0.' '_aSmallInteger2 := _aSStack1 firstLinkStack.' '_aSmallInteger3 := 5.').
 	testCase addMessage: #push: from: #SStack.
 	insertedExpression := expression
 		insertAsParameter: expression
 		using: testCase.
 	self
 		assert: insertedExpression printString
-		equals: '_var4 := _var1 push: _var2.'
+		equals: '_aSmallInteger4 := _aSStack1 push: _aSmallInteger2.'
 ]
 
 { #category : #tests }
@@ -54,10 +54,10 @@ SFieldAccessMessageTest >> testInsertRandomMessageUsing [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 score.').
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallFloat642 := _aSFoo1 score.').
 	aExpression insertRandomMessage: aExpression using: testCase.
 	self
 		assertCollection: (testCase statements collect: #printString)
 		includesAll:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 score.' '_var3 := _var1 score.')
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallFloat642 := _aSFoo1 score.' '_aSmallFloat643 := _aSFoo1 score.')
 ]
diff --git a/src/SmallSuiteGenerator-Tests/SInsertTest.class.st b/src/SmallSuiteGenerator-Tests/SInsertTest.class.st
index 8485fc6..6a05be5 100644
--- a/src/SmallSuiteGenerator-Tests/SInsertTest.class.st
+++ b/src/SmallSuiteGenerator-Tests/SInsertTest.class.st
@@ -23,10 +23,10 @@ SInsertTest >> testInsertStatementAsParameterInMessage [
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
 			(Array
-				with: '_var0 := SFoo new.'
-				with: '_var1 := ' , SStudent new storeString , '.'
-				with: '_var2 := _var0 return: _var1.'
-				with: '_var3 := ' , SStudent new storeString , '.').
+				with: '_aSFoo0 := SFoo new.'
+				with: '_aSStudent1 := ' , SStudent new storeString , '.'
+				with: '_aSStudent2 := _aSFoo0 return: _aSStudent1.'
+				with: '_aSStudent3 := ' , SStudent new storeString , '.').
 	self
 		should: [ testCase
 				perform: #insertAsParameter:using:
@@ -40,11 +40,11 @@ SInsertTest >> testInsertStatementAsParameterInMessage [
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
 			(Array
-				with: '_var0 := SFoo new.'
-				with: '_var1 := ' , SStudent new storeString , '.'
-				with: '_var2 := _var0 return: _var1.'
-				with: '_var3 := ' , SStudent new storeString , '.'
-				with: '_var4 := _var0 return: _var3.')
+				with: '_aSFoo0 := SFoo new.'
+				with: '_aSStudent1 := ' , SStudent new storeString , '.'
+				with: '_aSStudent2 := _aSFoo0 return: _aSStudent1.'
+				with: '_aSStudent3 := ' , SStudent new storeString , '.'
+				with: '_aSStudent4 := _aSFoo0 return: _aSStudent3.')
 ]
 
 { #category : #'mutation-insert' }
@@ -61,23 +61,23 @@ SInsertTest >> testInsertStatementOfMixingSelectors [
 	self
 		assertCollection: (testCase statements collect: #printString) allButLast
 		hasSameElements:
-			#('_var0 := 1.' '_var1 := SStudent new.' '_var2 := _var1 scoreStudent: _var0.' '_var3 := SStudent new.').
+			#('_aSmallInteger0 := 1.' '_aSStudent1 := SStudent new.' '_aSStudent2 := _aSStudent1 scoreStudent: _aSmallInteger0.' '_aSStudent3 := SStudent new.').
 	self
 		assert:
-			(#('_var4 := _var1 idStudent.' '_var4 := _var2 idStudent.' '_var4 := _var3 idStudent.')
-				includes: (testCase statementOfVarName: '_var4') printString).
-	fieldAccess := testCase statementOfVarName: '_var4'.
-	message := (testCase statementOfVarName: '_var2') value.
+			(#('_aSmallInteger4 := _aSStudent1 idStudent.' '_aSmallInteger4 := _aSStudent2 idStudent.' '_aSmallInteger4 := _var3 idStudent.')
+				includes: (testCase statementOfVarName: '_aSmallInteger4') printString).
+	fieldAccess := testCase statementOfVarName: '_aSmallInteger4'.
+	message := (testCase statementOfVarName: '_aSStudent2') value.
 	message := testCase insertExpression: message copy after: fieldAccess.
 	self
 		assert: message printString
-		equals: '_var5 := _var1 scoreStudent: _var0.'.
+		equals: '_aSStudent5 := _aSStudent1 scoreStudent: _aSmallInteger0.'.
 	message := testCase
 		perform: #insertAsParameter:using:
 		inStatement: fieldAccess.
 	self
 		assert: message printString
-		equals: '_var5 := _var1 scoreStudent: _var4.'
+		equals: '_aSStudent5 := _aSStudent1 scoreStudent: _aSmallInteger4.'
 ]
 
 { #category : #'mutation-insert' }
@@ -89,16 +89,16 @@ SInsertTest >> testInsertStatementOfSelectorAsParameterInFactoryMessage [
 	testCase addFactoryMessage.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := SFoo new.' '_var1 := SFoo new.').
+		hasSameElements: #('_aSFoo0 := SFoo new.' '_aSFoo1 := SFoo new.').
 	auxExpr := testCase addMessage.
 	auxExpr value
-		receiver: (testCase statementOfVarName: '_var1') variable.
+		receiver: (testCase statementOfVarName: '_aSFoo1') variable.
 	auxExpr := testCase
 		perform: #insertAsParameter:using:
 		inStatement: expression.
 	self
 		assert: auxExpr printString
-		equals: '_var2 := _var1 return: _var0.'
+		equals: '_aSFoo2 := _aSFoo1 return: _aSFoo0.'
 ]
 
 { #category : #'mutation-insert' }
@@ -113,7 +113,7 @@ SInsertTest >> testInsertStatementOfSelectorAsParameterInFieldMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := SStack newStack.' '_var1 := _var0 lastLinkStack.' '_var2 := 5.').
+			#('_aSStack0 := SStack newStack.' '_aSmallInteger1 := _aSStack0 lastLinkStack.' '_aSmallInteger2 := 5.').
 	testCase addMessage: #push: from: #SStack.
 	testCase
 		perform: #insertAsParameter:using:
@@ -121,7 +121,7 @@ SInsertTest >> testInsertStatementOfSelectorAsParameterInFieldMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := SStack newStack.' '_var1 := _var0 lastLinkStack.' '_var2 := 5.' '_var3 := _var0 push: _var1.')
+			#('_aSStack0 := SStack newStack.' '_aSmallInteger1 := _aSStack0 lastLinkStack.' '_aSmallInteger2 := 5.' '_aSmallInteger3 := _aSStack0 push: _aSmallInteger1.')
 ]
 
 { #category : #'mutation-insert' }
@@ -134,7 +134,7 @@ SInsertTest >> testInsertStatementOfSelectorAsParameterInMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := #(1 4 5 ).' '_var1 := SStack newStackWith: _var0.' '_var2 := _var1 pop.' '_var3 := 5.').
+			#('_anArray0 := #(1 4 5 ).' '_aSStack1 := SStack newStackWith: _anArray0.' '_aSmallInteger2 := _aSStack1 pop.' '_aSmallInteger3 := 5.').
 	testCase addMessage: #push: from: #SStack.
 	testCase
 		perform: #insertAsParameter:using:
@@ -142,7 +142,7 @@ SInsertTest >> testInsertStatementOfSelectorAsParameterInMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := #(1 4 5 ).' '_var1 := SStack newStackWith: _var0.' '_var2 := _var1 pop.' '_var3 := 5.' '_var4 := _var1 push: _var2.')
+			#('_anArray0 := #(1 4 5 ).' '_aSStack1 := SStack newStackWith: _anArray0.' '_aSmallInteger2 := _aSStack1 pop.' '_aSmallInteger3 := 5.' '_aSmallInteger4 := _aSStack1 push: _aSmallInteger2.')
 ]
 
 { #category : #'mutation-insert' }
@@ -153,7 +153,7 @@ SInsertTest >> testInsertStatementOfSelectorMethodMessageInFactoryMessage [
 	addFactoryMessage.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.').
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.').
 	self
 		should: [ testCase insertStatementOfSelector: #insertMethodMessage:using: ]
 		raise: SError
@@ -168,7 +168,7 @@ SInsertTest >> testInsertStatementOfSelectorMethodMessageInFieldMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 score.').
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallFloat642 := _aSFoo1 score.').
 	self
 		should: [ testCase
 				perform: #insertMethodMessage:using:
@@ -183,7 +183,7 @@ SInsertTest >> testInsertStatementOfSelectorMethodMessageInLiteral [
 	testCase addLiteral: #SmallInteger.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 5.').
+		hasSameElements: #('_aSmallInteger0 := 5.').
 	self
 		should: [ testCase insertStatementOfSelector: #insertMethodMessage:using: ]
 		raise: SError
@@ -198,14 +198,14 @@ SInsertTest >> testInsertStatementOfSelectorMethodMessageInMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 returnNum.').
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallInteger2 := _aSFoo1 returnNum.').
 	testCase
 		perform: #insertMethodMessage:using:
 		inStatement: message copy.
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 returnNum.' '_var3 := _var1 returnNum.')
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallInteger2 := _aSFoo1 returnNum.' '_aSmallInteger3 := _aSFoo1 returnNum.')
 ]
 
 { #category : #'mutation-insert' }
@@ -216,12 +216,12 @@ SInsertTest >> testInsertStatementOfSelectorRandomMessageInFactoryMessage [
 	addFactoryMessage.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.').
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.').
 	testCase insertStatementOfSelector: #insertRandomMessage:using:.
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := SFoo score: _var0.')
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSFoo2 := SFoo score: _aSmallFloat640.')
 ]
 
 { #category : #'mutation-insert' }
@@ -233,14 +233,14 @@ SInsertTest >> testInsertStatementOfSelectorRandomMessageInFieldMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 score.').
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallFloat642 := _aSFoo1 score.').
 	testCase
 		perform: #insertRandomMessage:using:
 		inStatement: fieldMessage copy.
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 score.' '_var3 := _var1 score.')
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallFloat642 := _aSFoo1 score.' '_aSmallFloat643 := _aSFoo1 score.')
 ]
 
 { #category : #'mutation-insert' }
@@ -250,7 +250,7 @@ SInsertTest >> testInsertStatementOfSelectorRandomMessageInLiteral [
 	testCase addLiteral: #SmallFloat64.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.').
+		hasSameElements: #('_aSmallFloat640 := 7.3.').
 	self
 		should: [ testCase insertStatementOfSelector: #insertRandomMessage:using: ]
 		raise: SError
@@ -265,12 +265,12 @@ SInsertTest >> testInsertStatementOfSelectorRandomMessageInMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 return: _var2.').
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 return: _aByteString2.').
 	testCase
 		perform: #insertRandomMessage:using:
 		inStatement: message copy.
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 return: _var2.' '_var4 := _var1 return: _var2.')
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 return: _aByteString2.' '_aByteString4 := _aSFoo1 return: _aByteString2.')
 ]
diff --git a/src/SmallSuiteGenerator-Tests/SLiteralTest.class.st b/src/SmallSuiteGenerator-Tests/SLiteralTest.class.st
index c4f614f..a56298a 100644
--- a/src/SmallSuiteGenerator-Tests/SLiteralTest.class.st
+++ b/src/SmallSuiteGenerator-Tests/SLiteralTest.class.st
@@ -37,14 +37,14 @@ SLiteralTest >> testInsertAsParameterUsing [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := ''hello''.' '_var1 := ''hello''.' '_var2 := 7.3.' '_var3 := SFoo score: _var2.').
+			#('_aByteString0 := ''hello''.' '_aByteString1 := ''hello''.' '_aSmallFloat642 := 7.3.' '_aSFoo3 := SFoo score: _aSmallFloat642.').
 	testCase addMessage: #return: from: #SFoo.
 	insertedExpression := expression
 		insertAsParameter: expression
 		using: testCase.
 	self
 		assert: insertedExpression printString
-		equals: '_var4 := _var3 return: _var1.'
+		equals: '_aByteString4 := _aSFoo3 return: _aByteString1.'
 ]
 
 { #category : #tests }
@@ -56,9 +56,9 @@ SLiteralTest >> testInsertParameterOn [
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
 			(Array
-				with: '_var0 := ' , SStudent new storeString , '.'
-				with: '_var1 := SFoo new.'
-				with: '_var2 := _var1 return: _var0.').
+				with: '_aSStudent0 := ' , SStudent new storeString , '.'
+				with: '_aSFoo1 := SFoo new.'
+				with: '_aSStudent2 := _aSFoo1 return: _aSStudent0.').
 	expression := testCase addLiteral: #SStudent.
 	self
 		should: [ insertedExpression := expression
@@ -73,7 +73,7 @@ SLiteralTest >> testInsertParameterOn [
 		raise: SError.
 	self
 		assert: insertedExpression printString
-		equals: '_var4 := _var1 return: _var3.'
+		equals: '_aSStudent4 := _aSFoo1 return: _aSStudent3.'
 ]
 
 { #category : #tests }
diff --git a/src/SmallSuiteGenerator-Tests/SMessageTest.class.st b/src/SmallSuiteGenerator-Tests/SMessageTest.class.st
index 19378e4..7530497 100644
--- a/src/SmallSuiteGenerator-Tests/SMessageTest.class.st
+++ b/src/SmallSuiteGenerator-Tests/SMessageTest.class.st
@@ -17,16 +17,16 @@ SMessageTest >> testCopy [
 						id: 2;
 						returnType: #ByteString));
 		returnType: #ByteString.
-	self assert: message printString equals: '_var1 return: _var2'.
+	self assert: message printString equals: '_aSFoo1 return: _aByteString2'.
 	copy := message copy.
 	copy value args first id: 5.
-	self assert: copy printString equals: '_var1 return: _var5'.
+	self assert: copy printString equals: '_aSFoo1 return: _aByteString5'.
 	copy value receiver varName: '_sfoo'.
 	copy value receiver id: 4.
-	self assert: copy printString equals: '_sfoo4 return: _var5'.
+	self assert: copy printString equals: '_sfoo4 return: _aByteString5'.
 	copy value selector: #returnValue:.
-	self assert: copy printString equals: '_sfoo4 returnValue: _var5'.
-	self assert: message printString equals: '_var1 return: _var2'
+	self assert: copy printString equals: '_sfoo4 returnValue: _aByteString5'.
+	self assert: message printString equals: '_aSFoo1 return: _aByteString2'
 ]
 
 { #category : #tests }
@@ -38,14 +38,14 @@ SMessageTest >> testInsertAsParameterUsing [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 returnString.').
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 returnString.').
 	testCase addMessage: #return: from: #SFoo.
 	insertedExpression := aExpression
 		insertAsParameter: aExpression
 		using: testCase.
 	self
 		assert:
-			(#('_var4 := _var1 return: _var3.')
+			(#('_aByteString4 := _aSFoo1 return: _aByteString3.')
 				includes: insertedExpression printString)
 ]
 
@@ -58,10 +58,10 @@ SMessageTest >> testInsertMethodMessageUsing [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 return: _var2.').
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 return: _aByteString2.').
 	message insertMethodMessage: message using: testCase.
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 return: _var2.' '_var4 := _var1 return: _var2.')
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 return: _aByteString2.' '_aByteString4 := _aSFoo1 return: _aByteString2.')
 ]
diff --git a/src/SmallSuiteGenerator-Tests/SMutatorTestCaseTest.class.st b/src/SmallSuiteGenerator-Tests/SMutatorTestCaseTest.class.st
index dd988b6..f5039a2 100644
--- a/src/SmallSuiteGenerator-Tests/SMutatorTestCaseTest.class.st
+++ b/src/SmallSuiteGenerator-Tests/SMutatorTestCaseTest.class.st
@@ -21,9 +21,9 @@ SMutatorTestCaseTest >> testRemoveArgsMethod [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 return: _var2.').
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 return: _aByteString2.').
 	numExprsBefore := testCase numberStatements.
-	expression := testCase statementOfVarName: '_var2'.
+	expression := testCase statementOfVarName: '_aByteString2'.
 	testCase removeExpression: expression.
 	numExprsAfter := testCase numberStatements.
 	self assert: numExprsAfter equals: numExprsBefore
@@ -46,12 +46,12 @@ SMutatorTestCaseTest >> testRemoveExpressionWithoutRepairing [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 return: _var2.').
-	expression := testCase statementOfVarName: '_var2'.
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 return: _aByteString2.').
+	expression := testCase statementOfVarName: '_aByteString2'.
 	testCase removeExpressionWithoutRepairing: expression.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.')
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.')
 ]
 
 { #category : #tests }
@@ -69,18 +69,18 @@ SMutatorTestCaseTest >> testRepair [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 return: _var2.').
-	expression := testCase statementOfVarName: '_var2'.
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 return: _aByteString2.').
+	expression := testCase statementOfVarName: '_aByteString2'.
 	self should: [ testCase repair: expression ] raise: SError.
 	testCase removeFromStatements: expression.
 	self assert: (testCase repair: expression) isEmpty.
-	expression := testCase statementOfVarName: '_var3'.
+	expression := testCase statementOfVarName: '_aByteString3'.
 	self
 		assertCollection: (expression value args collect: #printString)
-		hasSameElements: #('_var4').
+		hasSameElements: #('_aByteString4').
 	self
 		assert:
 			(((testCase subStatementsFrom: 1 toPrevIndexOf: expression)
 				collect: #printString)
-				includesAny: #('_var4 := ''hello''.' '_var4 := _var1 returnString.'))
+				includesAny: #('_aByteString4 := ''hello''.' '_aByteString4 := _aSFoo1 returnString.'))
 ]
diff --git a/src/SmallSuiteGenerator-Tests/SRemoveTest.class.st b/src/SmallSuiteGenerator-Tests/SRemoveTest.class.st
index d2ec542..11f4351 100644
--- a/src/SmallSuiteGenerator-Tests/SRemoveTest.class.st
+++ b/src/SmallSuiteGenerator-Tests/SRemoveTest.class.st
@@ -13,11 +13,11 @@ SRemoveTest >> testRemoveArgsFactoryMessage [
 		addFactoryMessage.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.').
-	testCase removeStatementOfVarName: '_var0'.
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.').
+	testCase removeStatementOfVarName: '_aSmallFloat640'.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var2 := 7.3.' '_var1 := SFoo score: _var2.').
+		hasSameElements: #('_aSmallFloat642 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat642.').
 	self assert: testCase validReferences
 ]
 
@@ -30,15 +30,15 @@ SRemoveTest >> testRemoveArgsMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 return: _var2.').
-	testCase removeStatementOfVarName: '_var2'.
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 return: _aByteString2.').
+	testCase removeStatementOfVarName: '_aByteString2'.
 	self
 		assert:
-			(#('_var4 := ''hello''.' '_var4 := _var1 returnString.')
-				includes: (testCase statementOfVarName: '_var4') printString).
+			(#('_aByteString4 := ''hello''.' '_aByteString4 := _aSFoo1 returnString.')
+				includes: (testCase statementOfVarName: '_aByteString4') printString).
 	self
-		assert: (testCase statementOfVarName: '_var3') printString
-		equals: '_var3 := _var1 return: _var4.'.
+		assert: (testCase statementOfVarName: '_aByteString3') printString
+		equals: '_aByteString3 := _aSFoo1 return: _aByteString4.'.
 	self assert: testCase validReferences
 ]
 
@@ -50,11 +50,11 @@ SRemoveTest >> testRemoveFactoryMessage [
 	addFactoryMessage.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.').
-	testCase removeStatementOfVarName: '_var1'.
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.').
+	testCase removeStatementOfVarName: '_aSFoo1'.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.')
+		hasSameElements: #('_aSmallFloat640 := 7.3.')
 ]
 
 { #category : #'mutation-remove' }
@@ -66,11 +66,11 @@ SRemoveTest >> testRemoveFieldAccessMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 score.').
-	testCase removeStatementOfVarName: '_var2'.
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallFloat642 := _aSFoo1 score.').
+	testCase removeStatementOfVarName: '_aSmallFloat642'.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.')
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.')
 ]
 
 { #category : #'mutation-remove' }
@@ -82,11 +82,11 @@ SRemoveTest >> testRemoveMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 return: _var2.').
-	testCase removeStatementOfVarName: '_var3'.
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 return: _aByteString2.').
+	testCase removeStatementOfVarName: '_aByteString3'.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.')
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.')
 ]
 
 { #category : #'mutation-remove' }
@@ -98,12 +98,12 @@ SRemoveTest >> testRemoveReceiverFieldAccessMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 score.').
-	testCase removeStatementOfVarName: '_var1'.
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallFloat642 := _aSFoo1 score.').
+	testCase removeStatementOfVarName: '_aSFoo1'.
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var3 := SFoo score: _var0.' '_var2 := _var3 score.')
+			#('_aSmallFloat640 := 7.3.' '_aSFoo3 := SFoo score: _aSmallFloat640.' '_aSmallFloat642 := _aSFoo3 score.')
 ]
 
 { #category : #'mutation-remove' }
@@ -115,12 +115,12 @@ SRemoveTest >> testRemoveReceiverMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var1 return: _var2.').
-	testCase removeStatementOfVarName: '_var1'.
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo1 return: _aByteString2.').
+	testCase removeStatementOfVarName: '_aSFoo1'.
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var4 := SFoo score: _var0.' '_var2 := ''hello''.' '_var3 := _var4 return: _var2.')
+			#('_aSmallFloat640 := 7.3.' '_aSFoo4 := SFoo score: _aSmallFloat640.' '_aByteString2 := ''hello''.' '_aByteString3 := _aSFoo4 return: _aByteString2.')
 ]
 
 { #category : #'mutation-remove' }
@@ -131,11 +131,11 @@ SRemoveTest >> testRemoveStatementNoRepairing [
 	statement := testCase addFactoryMessage.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.' '_var1 := SFoo score: _var0.').
+		hasSameElements: #('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.').
 	testCase removeStatementNoRepairing: statement.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.').
+		hasSameElements: #('_aSmallFloat640 := 7.3.').
 	testCase := SSTestCase with: utility typeInfoSFoo1.
 	testCase addTargetClassName: #SFoo.
 	statement := testCase addFactoryMessage.
@@ -143,9 +143,9 @@ SRemoveTest >> testRemoveStatementNoRepairing [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 returnFloat.').
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallFloat642 := _aSFoo1 returnFloat.').
 	testCase removeStatementNoRepairing: statement.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 7.3.')
+		hasSameElements: #('_aSmallFloat640 := 7.3.')
 ]
diff --git a/src/SmallSuiteGenerator-Tests/SSTestCaseTest.class.st b/src/SmallSuiteGenerator-Tests/SSTestCaseTest.class.st
index fb14380..70f1ad8 100644
--- a/src/SmallSuiteGenerator-Tests/SSTestCaseTest.class.st
+++ b/src/SmallSuiteGenerator-Tests/SSTestCaseTest.class.st
@@ -54,11 +54,11 @@ SSTestCaseTest >> testCopy [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 returnNum.' '_var3 := _var1 score.' '_var4 := 5.' '_var5 := ''hello''.').
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallInteger2 := _aSFoo1 returnNum.' '_aSmallInteger3 := _aSFoo1 score.' '_aSmallInteger4 := 5.' '_aByteString5 := ''hello''.').
 	self
 		assertCollection: (otherTestCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 7.3.' '_var1 := SFoo score: _var0.' '_var2 := _var1 returnNum.' '_var3 := _var1 score.' '_var4 := 5.' '_var5 := _var1 returnFloat.' '_var6 := ''hello''.' '_var7 := _var1 return: _var6.')
+			#('_aSmallFloat640 := 7.3.' '_aSFoo1 := SFoo score: _aSmallFloat640.' '_aSmallInteger2 := _aSFoo1 returnNum.' '_aSmallInteger3 := _aSFoo1 score.' '_aSmallInteger4 := 5.' '_aSmallFloat645 := _aSFoo1 returnFloat.' '_aByteString6 := ''hello''.' '_aByteString7 := _aSFoo1 return: _aByteString6.')
 ]
 
 { #category : #tests }
@@ -83,7 +83,7 @@ SSTestCaseTest >> testFieldAccessMessage [
 	self assert: testCase statements size equals: 3.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 5.' '_var1 := SFoo score: _var0.' '_var2 := _var1 score.')
+		hasSameElements: #('_aSmallInteger0 := 5.' '_aSFoo1 := SFoo score: _aSmallInteger0.' '_aSmallInteger2 := _aSFoo1 score.')
 ]
 
 { #category : #tests }
diff --git a/src/SmallSuiteGenerator-Tests/SSTestShifterTest.class.st b/src/SmallSuiteGenerator-Tests/SSTestShifterTest.class.st
index ef0f7ae..36ff228 100644
--- a/src/SmallSuiteGenerator-Tests/SSTestShifterTest.class.st
+++ b/src/SmallSuiteGenerator-Tests/SSTestShifterTest.class.st
@@ -39,7 +39,7 @@ SSTestShifterTest >> testAddFactoryMessage [
 	self assert: testCase statements size equals: 2.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 4.' '_var1 := SFoo score: _var0.').
+		hasSameElements: #('_aSmallInteger0 := 4.' '_aSFoo1 := SFoo score: _aSmallInteger0.').
 	self should: [ testCase addFactoryMessage: #SStack ] raise: SError.
 	aTypeInfo
 		type:
@@ -55,7 +55,7 @@ SSTestShifterTest >> testAddFactoryMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 4.' '_var1 := SFoo score: _var0.' '_var2 := #(1 3 2 ).' '_var3 := SStack newStack: _var2.')
+			#('_aSmallInteger0 := 4.' '_aSFoo1 := SFoo score: _aSmallInteger0.' '_anArray2 := #(1 3 2 ).' '_aSStack3 := SStack newStack: _anArray2.')
 ]
 
 { #category : #tests }
@@ -67,7 +67,7 @@ SSTestShifterTest >> testAddFactoryMessageOfInexistentSelector [
 		addFactoryMessage: #SFoo ofSelector: #score:.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := SFoo new.')
+		hasSameElements: #('_aSFoo0 := SFoo new.')
 ]
 
 { #category : #tests }
@@ -79,7 +79,7 @@ SSTestShifterTest >> testAddFactoryMessageOfSelector [
 		addFactoryMessage: #SFoo ofSelector: #score:.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 4.' '_var1 := SFoo score: _var0.')
+		hasSameElements: #('_aSmallInteger0 := 4.' '_aSFoo1 := SFoo score: _aSmallInteger0.')
 ]
 
 { #category : #tests }
@@ -91,14 +91,14 @@ SSTestShifterTest >> testAddFactoryMessageOnPackage [
 	expression := testCase addFactoryMessage: #SSTeacher.
 	self
 		assert:
-			(#('_var2 := SSTeacher name: _var0 with: _var1.' '_var2 := SSTeacher name: _var1 with: _var0.')
+			(#('_aSSTeacher2 := SSTeacher name: _aByteString0 with: _aSmallInteger1.' '_aSSTeacher2 := SSTeacher name: _aByteString1 with: _aSmallInteger0.')
 				includes: expression printString).
 	self
 		shouldnt: [ expression := testCase addFactoryMessage: #SConference ]
 		raise: SError.
 	self
 		assert: expression printString
-		equals: '_var3 := SConference new.'
+		equals: '_aSConference3 := SConference new.'
 ]
 
 { #category : #tests }
@@ -122,7 +122,7 @@ SSTestShifterTest >> testAddFieldAccessMessage [
 	testCase addTargetClassName: #SSTeacher.
 	self
 		assert: testCase addFieldAccessMessage printString
-		equals: '_var1 := _var0 idTeacher.'.
+		equals: '_aSmallInteger1 := _aSSTeacher0 idTeacher.'.
 ]
 
 { #category : #tests }
@@ -135,7 +135,7 @@ SSTestShifterTest >> testAddFieldAccessMessageFrom [
 	testCase addTargetClassName: #SFoo.
 	self
 		assert: (testCase addFieldAccessMessage: #score from: #SFoo) printString
-		equals: '_var2 := _var1 score.'
+		equals: '_aSmallInteger2 := _aSFoo1 score.'
 ]
 
 { #category : #tests }
@@ -184,7 +184,7 @@ SSTestShifterTest >> testAddFieldAccessMessageWithReceiver [
 			(testCase
 				addFieldAccessMessage: (typeInfo accessMessagesFrom: #SFoo) first
 				withReceiver: receiver) printString
-		equals: '_var2 := _var1 score.'
+		equals: '_aSmallFloat642 := _aSFoo1 score.'
 ]
 
 { #category : #tests }
@@ -219,16 +219,16 @@ SSTestShifterTest >> testAddLiteral [
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
 			(Array
-				with: '_var0 := ''World''.'
+				with: '_aByteString0 := ''World''.'
 				with:
-					'_var1 := '
+					'_anOrderedCollection1 := '
 						,
 							(OrderedCollection new
 								add: 1;
 								add: 4;
 								yourself) storeString , '.'
-				with: '_var2 := 2.'
-				with: '_var3 := ' , SStudent new storeString , '.')
+				with: '_aSmallInteger2 := 2.'
+				with: '_aSStudent3 := ' , SStudent new storeString , '.')
 ]
 
 { #category : #tests }
@@ -259,9 +259,9 @@ SSTestShifterTest >> testAddMessage [
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
 			(Array
-				with: '_var0 := SFoo new.'
-				with: '_var1 := ' , (OrderedCollection newFrom: #(1 4 5)) storeString , '.'
-				with: '_var2 := _var0 return: _var1.')
+				with: '_aSFoo0 := SFoo new.'
+				with: '_anOrderedCollection1 := ' , (OrderedCollection newFrom: #(1 4 5)) storeString , '.'
+				with: '_anOrderedCollection2 := _aSFoo0 return: _anOrderedCollection1.')
 ]
 
 { #category : #tests }
@@ -276,15 +276,15 @@ SSTestShifterTest >> testAddMessageFrom [
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
 			(Array
-				with: '_var0 := 4.'
-				with: '_var1 := SFoo score: _var0.'
-				with: '_var2 := _var1 returnFloat.').
+				with: '_aSmallInteger0 := 4.'
+				with: '_aSFoo1 := SFoo score: _aSmallInteger0.'
+				with: '_aSmallFloat642 := _aSFoo1 returnFloat.').
 	self
 		assert: (testCase addMessage: #returnNum from: #SFoo) printString
-		equals: '_var3 := _var1 returnNum.'.
+		equals: '_aSmallInteger3 := _aSFoo1 returnNum.'.
 	self
 		assert:
-			(#('_var4 := _var1 score: _var0.' '_var4 := _var1 score: _var3.')
+			(#('_aSFoo4 := _aSFoo1 score: _aSmallInteger0.' '_aSFoo4 := _aSFoo1 score: _aSmallInteger3.')
 				includes: (testCase addMessage: #score: from: #SFoo) printString)
 ]
 
@@ -303,9 +303,9 @@ SSTestShifterTest >> testAddMessageFromDifferentReceiver [
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
 			(Array
-				with: '_var0 := SConference new.'
-				with: '_var1 := ' , (SStudent new name: 'Mary') storeString , '.'
-				with: '_var2 := _var0 canRegister: _var1.')
+				with: '_aSConference0 := SConference new.'
+				with: '_aSStudent1 := ' , (SStudent new name: 'Mary') storeString , '.'
+				with: '_aFalse2 := _aSConference0 canRegister: _aSStudent1.')
 ]
 
 { #category : #tests }
@@ -327,7 +327,7 @@ SSTestShifterTest >> testAddMessageWithReceiver [
 			(testCase
 				addMessage: (typeInfo messagesFrom: #SFoo) first
 				withReceiver: receiver) printString
-		equals: '_var1 := _var0 return: _var0.'
+		equals: '_aSFoo1 := _aSFoo0 return: _aSFoo0.'
 ]
 
 { #category : #tests }
@@ -343,17 +343,17 @@ SSTestShifterTest >> testAddMessageWithTwoDeepScalarSFoo [
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
 			(OrderedCollection new
-				add: '_var0 := SFoo new.';
-				add: '_var1 := ' , (SStudent name: 'Lian' with: 1) storeString , '.';
-				add: '_var2 := SStack new.';
-				add: '_var3 := _var2 push: _var1.';
-				add: '_var4 := ' , (SStudent name: 'Josh' with: 2) storeString , '.';
-				add: '_var5 := _var2 push: _var4.';
-				add: '_var6 := ' , (SStudent name: 'Mery' with: 5) storeString , '.';
-				add: '_var7 := ((OrderedCollection new) add: _var6; yourself).';
+				add: '_aSFoo0 := SFoo new.';
+				add: '_aSStudent1 := ' , (SStudent name: 'Lian' with: 1) storeString , '.';
+				add: '_aSStack2 := SStack new.';
+				add: '_aSStudent3 := _aSStack2 push: _aSStudent1.';
+				add: '_aSStudent4 := ' , (SStudent name: 'Josh' with: 2) storeString , '.';
+				add: '_aSStudent5 := _aSStack2 push: _aSStudent4.';
+				add: '_aSStudent6 := ' , (SStudent name: 'Mery' with: 5) storeString , '.';
+				add: '_anOrderedCollection7 := ((OrderedCollection new) add: _aSStudent6; yourself).';
 				add:
-					'_var8 := ((Dictionary new) add: (1->_var5); add: (2->_var7); yourself).';
-				add: '_var9 := _var0 return: _var8.';
+					'_aDictionary8 := ((Dictionary new) add: (1->_aSStudent5); add: (2->_anOrderedCollection7); yourself).';
+				add: '_aDictionary9 := _aSFoo0 return: _aDictionary8.';
 				yourself)
 ]
 
@@ -373,18 +373,18 @@ SSTestShifterTest >> testAddMessageWithTwoDeepScalarSStack [
 					(Array
 						with:
 							(OrderedCollection new
-								add: '_var0 := SStack new.';
-								add: '_var1 := ' , (SStudent name: 'Lian' with: 1) storeString , '.';
-								add: '_var2 := ' , (SStudent name: 'Josh' with: 2) storeString , '.';
-								add: '_var3 := ((OrderedCollection new) add: _var1; add: _var2; yourself).';
-								add: '_var4 := _var0 push: _var3.';
+								add: '_aSStack0 := SStack new.';
+								add: '_aSStudent1 := ' , (SStudent name: 'Lian' with: 1) storeString , '.';
+								add: '_aSStudent2 := ' , (SStudent name: 'Josh' with: 2) storeString , '.';
+								add: '_anOrderedCollection3 := ((OrderedCollection new) add: _aSStudent1; add: _aSStudent2; yourself).';
+								add: '_anOrderedCollection4 := _aSStack0 push: _anOrderedCollection3.';
 								yourself)
 						with:
 							(OrderedCollection new
-								add: '_var0 := SStack new.';
-								add: '_var1 := ' , (SStudent name: 'Mery' with: 5) storeString , '.';
-								add: '_var2 := ((OrderedCollection new) add: _var1; yourself).';
-								add: '_var3 := _var0 push: _var2.';
+								add: '_aSStack0 := SStack new.';
+								add: '_aSStudent1 := ' , (SStudent name: 'Mery' with: 5) storeString , '.';
+								add: '_anOrderedCollection2 := ((OrderedCollection new) add: _aSStudent1; yourself).';
+								add: '_anOrderedCollection3 := _aSStack0 push: _anOrderedCollection2.';
 								yourself)))
 ]
 
@@ -480,14 +480,14 @@ SSTestShifterTest >> testAddStatetementOfTypeBefore [
 	expression := testCase addStatementOfType: #SEvent before: nil.
 	self
 		assert: expression printString
-		equals: '_var1 := SEvent price: _var0.'.
+		equals: '_aSEvent1 := SEvent price: _aSmallInteger0.'.
 	expression := testCase
 		addStatementOfType: #SmallInteger
 		before: expression.
-	self assert: expression printString equals: '_var2 := 8.'.	"change the form to select randomly"
+	self assert: expression printString equals: '_aSmallInteger2 := 8.'.	"change the form to select randomly"
 	self
 		assert:
-			(#(#('_var0 := 8.' '_var2 := 8.' '_var1 := SEvent price: _var0.') #('_var2 := 8.' '_var0 := 8.' '_var1 := SEvent price: _var0.'))
+			(#(#('_aSmallInteger0 := 8.' '_aSmallInteger2 := 8.' '_aSEvent1 := SEvent price: _aSmallInteger0.') #('_aSmallInteger2 := 8.' '_aSmallInteger0 := 8.' '_aSEvent1 := SEvent price: _aSmallInteger0.'))
 				includes: (testCase statements collect: #printString) asArray)
 ]
 
@@ -501,7 +501,7 @@ SSTestShifterTest >> testAddStatetementOfTypeBeforeFactoryMessage [
 	self
 		assertCollection: (testCase statements collect: #printString)
 		hasSameElements:
-			#('_var0 := 8.' '_var2 := SEvent price: _var0.' '_var1 := SEvent price: _var0.')
+			#('_aSmallInteger0 := 8.' '_aSEvent2 := SEvent price: _aSmallInteger0.' '_aSEvent1 := SEvent price: _aSmallInteger0.')
 ]
 
 { #category : #tests }
@@ -513,7 +513,7 @@ SSTestShifterTest >> testAddTargetClassName [
 	expression := testCase addFactoryMessage: #SSTeacher.
 	self
 		assert:
-			(#('_var2 := SSTeacher name: _var0 with: _var1.' '_var2 := SSTeacher name: _var1 with: _var0.')
+			(#('_aSSTeacher2 := SSTeacher name: _aByteString0 with: _aSmallInteger1.' '_aSSTeacher2 := SSTeacher name: _aByteString1 with: _aSmallInteger0.')
 				includes: expression printString).
 ]
 
@@ -527,7 +527,7 @@ SSTestShifterTest >> testBuildArgsBefore [
 	testCase buildArgs: ((typeInfo factoryMessagesFrom: #SEvent) first argTypes)  before: expression.
 	self
 		assertCollection: (testCase printStatements )
-		hasSameElements: #('_var1 := 8.' '_var0 := 8.')
+		hasSameElements: #('_aSmallInteger1 := 8.' '_aSmallInteger0 := 8.')
 ]
 
 { #category : #tests }
@@ -538,7 +538,7 @@ SSTestShifterTest >> testNewFactoryMessageBefore [
 	expression := testCase addLiteral.
 	self
 		assert: (testCase newFactoryMessage: #SEvent before: expression) printString
-		equals: 'SEvent price: _var1'.
+		equals: 'SEvent price: _aSmallInteger1'.
 	"default factoryMessage"
 	testCase := SSTestCase with: utility typeInfoSFoo5.
 	testCase addTargetClassName: #SFoo.
@@ -555,8 +555,8 @@ SSTestShifterTest >> testNewFactoryMessageUsingAnd [
 	expression := testCase addLiteral.
 	self
 		assert: (testCase newFactoryMessageUsing: #SEvent and: expression) printString
-		equals: 'SEvent price: _var1'.
-	self assertCollection: testCase printStatements  hasSameElements: #('_var1 := 8.' '_var0 := 8.')
+		equals: 'SEvent price: _aSmallInteger1'.
+	self assertCollection: testCase printStatements  hasSameElements: #('_aSmallInteger1 := 8.' '_aSmallInteger0 := 8.')
 ]
 
 { #category : #tests }
@@ -577,10 +577,10 @@ SSTestShifterTest >> testNewFieldAccessMessageOfTypeBefore [
 		assert:
 			(testCase newFieldAccessMessageOfType: #SmallFloat64 before: expression)
 				printString
-		equals: '_var2 score'.
+		equals: '_aSFoo2 score'.
 	self
 		assertCollection: testCase printStatements
-		hasSameElements: #('_var1 := 7.3.' '_var2 := SFoo score: _var1.' '_var0 := 5.')
+		hasSameElements: #('_aSmallFloat641 := 7.3.' '_aSFoo2 := SFoo score: _aSmallFloat641.' '_aSmallInteger0 := 5.')
 ]
 
 { #category : #tests }
@@ -601,10 +601,10 @@ SSTestShifterTest >> testNewMessageOfTypeBefore [
 		assert:
 			(testCase newMessageOfType: #SmallInteger before: expression)
 				printString
-		equals: '_var2 returnNum'.
+		equals: '_aSFoo2 returnNum'.
 	self
 		assertCollection: testCase printStatements
-		hasSameElements: #('_var1 := 7.3.' '_var2 := SFoo score: _var1.' '_var0 := 5.')
+		hasSameElements: #('_aSmallFloat641 := 7.3.' '_aSFoo2 := SFoo score: _aSmallFloat641.' '_aSmallInteger0 := 5.')
 ]
 
 { #category : #tests }
@@ -617,16 +617,16 @@ SSTestShifterTest >> testNewStatementOfTypeBefore [
 	testCase addStatement: expression before: nil.
 	self
 		assertCollection: testCase printStatements
-		hasSameElements: #('_var0 := 8.').
+		hasSameElements: #('_aSmallInteger0 := 8.').
 	expression := testCase newStatementOfType: #SEvent before: expression.
-	self assert: expression printString equals: 'SEvent price: _var1'.
+	self assert: expression printString equals: 'SEvent price: _aSmallInteger1'.
 	expression := testCase newAssignment: expression.
 	testCase
 		addStatement: expression
-		before: (testCase statementOfVarName: '_var0').
+		before: (testCase statementOfVarName: '_aSmallInteger0').
 	self
 		assertCollection: testCase printStatements
-		hasSameElements: #('_var1 := 8.' '_var2 := SEvent price: _var1.' '_var0 := 8.')
+		hasSameElements: #('_aSmallInteger1 := 8.' '_aSEvent2 := SEvent price: _aSmallInteger1.' '_aSmallInteger0 := 8.')
 ]
 
 { #category : #tests }
@@ -639,7 +639,7 @@ SSTestShifterTest >> testObjectVariables [
 		addFactoryMessage.
 	self
 		assertCollection: (testCase objectVariables collect: #printString)
-		hasSameElements: #('_var0')
+		hasSameElements: #('_aSSTeacher0')
 ]
 
 { #category : #tests }
@@ -670,7 +670,7 @@ SSTestShifterTest >> testPickAnObjectVariable [
 	testCase := SSTestCase with: utility typeInfoSSTeacher3.
 	self should: [testCase  pickAnObjectVariable ] raise: SError.
 	testCase addTargetClassName: #SSTeacher.
-	self assert: testCase pickAnObjectVariable printString equals: '_var0'
+	self assert: testCase pickAnObjectVariable printString equals: '_aSSTeacher0'
 ]
 
 { #category : #tests }
@@ -684,7 +684,7 @@ SSTestShifterTest >> testPickFactoryMessagesFrom [
 	testCase addFactoryMessage: #SConference ofSelector: #price:.
 	self
 		assertCollection: (testCase statements collect: #printString)
-		hasSameElements: #('_var0 := 95.' '_var1 := SConference price: _var0.')
+		hasSameElements: #('_aSmallInteger0 := 95.' '_aSConference1 := SConference price: _aSmallInteger0.')
 ]
 
 { #category : #tests }
@@ -720,8 +720,8 @@ SSTestShifterTest >> testPickOrCreateObjectVariableOf [
 	self assert: testCase statements isEmpty.
 	self
 		assert: (testCase pickOrCreateObjectVariableOf: #SFoo) printString
-		equals: '_var0'.
-	self assertCollection: (testCase statements collect: #printString) hasSameElements: #('_var0 := SFoo new.').
+		equals: '_aSFoo0'.
+	self assertCollection: (testCase statements collect: #printString) hasSameElements: #('_aSFoo0 := SFoo new.').
 	testCase pickOrCreateObjectVariableOf: #SFoo.
 	self assert: testCase statements size equals: 1
 ]
@@ -775,19 +775,19 @@ SSTestShifterTest >> testSubStatementsFromToPrevIndexOf [
 		assertCollection:
 			((testCase subStatementsFrom: 1 toPrevIndexOf: expression)
 				collect: #printString)
-		hasSameElements: #('_var0 := 8.').
+		hasSameElements: #('_aSmallInteger0 := 8.').
 	expression := testCase addMessage: #discount: from: #SEvent.
 	self
 		assertCollection:
 			((testCase subStatementsFrom: 1 toPrevIndexOf: expression)
 				collect: #printString)
-		hasSameElements: #('_var0 := 8.' '_var1 := SEvent price: _var0.').
+		hasSameElements: #('_aSmallInteger0 := 8.' '_aSEvent1 := SEvent price: _aSmallInteger0.').
 	expression := testCase addFieldAccessMessage: #price from: #SEvent.
 	self
 		assertCollection:
 			((testCase subStatementsFrom: 1 toPrevIndexOf: expression)
 				collect: #printString)
-		hasSameElements: #('_var0 := 8.' '_var1 := SEvent price: _var0.' '_var2 := _var1 discount: _var0.').
+		hasSameElements: #('_aSmallInteger0 := 8.' '_aSEvent1 := SEvent price: _aSmallInteger0.' '_aSEvent2 := _aSEvent1 discount: _aSmallInteger0.').
 ]
 
 { #category : #tests }
diff --git a/src/SmallSuiteGenerator/SFactoryMessage.class.st b/src/SmallSuiteGenerator/SFactoryMessage.class.st
index 99b52ef..fbfffb8 100644
--- a/src/SmallSuiteGenerator/SFactoryMessage.class.st
+++ b/src/SmallSuiteGenerator/SFactoryMessage.class.st
@@ -93,6 +93,13 @@ SFactoryMessage >> isFactoryMessage [
 	^ true
 ]
 
+{ #category : #printing }
+SFactoryMessage >> printOn: aStream [
+	(receiver returnType ifNil: [ receiver ] ifNotNil: [receiver returnType asClass]) printOn: aStream.
+	aStream	nextPut: Character space.
+	self printSelectors: aStream
+]
+
 { #category : #accessing }
 SFactoryMessage >> referenceTo: aClassName [
 	^ receiver referenceTo: aClassName
diff --git a/src/SmallSuiteGenerator/SSTestRunner.class.st b/src/SmallSuiteGenerator/SSTestRunner.class.st
index 22b2d18..a26880a 100644
--- a/src/SmallSuiteGenerator/SSTestRunner.class.st
+++ b/src/SmallSuiteGenerator/SSTestRunner.class.st
@@ -48,10 +48,26 @@ SSTestRunner >> initialize [
 
 { #category : #'as yet unclassified' }
 SSTestRunner >> performTest [
-	| _var0 _var1 |
-_var0 := RTGrapher new.
-_var1 := _var0 homogenizeMinAndMax.
-^self analyze: thisContext
+	| _aSStudent0 _aSStudent1 _aSmallInteger2 _aSmallInteger3 _aSmallInteger4 _aSmallInteger5 _aSStudent6 _aSStudent7 _aSStudent8 _aSStudent9 _aSStudent10 _aSmallInteger11 _aSmallInteger12 _aSmallInteger13 _aSStudent14 _aSmallInteger15 _aSStudent16 _aSStudent17 _aSmallInteger18 |
+_aSStudent0 := SStudent new.
+_aSStudent1 := _aSStudent0 initialize.
+_aSmallInteger2 := 1.
+_aSmallInteger3 := _aSStudent1 scoreStudent: _aSmallInteger2.
+_aSmallInteger4 := _aSStudent1 scoreStudent: _aSmallInteger3.
+_aSmallInteger5 := _aSStudent1 scoreStudent: _aSmallInteger2.
+_aSStudent6 := _aSStudent0 initialize.
+_aSStudent7 := _aSStudent6 initialize.
+_aSStudent8 := _aSStudent1 initialize.
+_aSStudent9 := _aSStudent8 initialize.
+_aSStudent10 := _aSStudent8 initialize.
+_aSmallInteger11 := _aSStudent8 scoreStudent: _aSmallInteger3.
+_aSmallInteger12 := _aSStudent8 scoreStudent: _aSmallInteger4.
+_aSmallInteger13 := _aSStudent0 scoreStudent: _aSmallInteger12.
+_aSStudent14 := _aSStudent8 initialize.
+_aSmallInteger15 := _aSStudent7 scoreStudent: _aSmallInteger2.
+_aSStudent16 := _aSStudent0 initialize.
+_aSStudent17 := _aSStudent1 initialize.
+_aSmallInteger18 := _aSStudent14 scoreStudent: _aSmallInteger12
 ]
 
 { #category : #running }
diff --git a/src/SmallSuiteGenerator/SVariable.class.st b/src/SmallSuiteGenerator/SVariable.class.st
index feb06bd..77c192e 100644
--- a/src/SmallSuiteGenerator/SVariable.class.st
+++ b/src/SmallSuiteGenerator/SVariable.class.st
@@ -113,6 +113,12 @@ SVariable >> replaceExpression: anExpression by: newExpression [
 		returnType: reference returnType
 ]
 
+{ #category : #accessing }
+SVariable >> returnType: anObject [
+	anObject ifNotNil: [varName := anObject first isVowel ifTrue: ['_an', anObject ] ifFalse: ['_a', anObject ]].
+	returnType := anObject.
+]
+
 { #category : #accessing }
 SVariable >> varName [
 	^ varName