diff --git a/test/function/builtin/APPLYTester.java b/test/function/builtin/APPLYTester.java
index 70338c3..3547ab3 100644
--- a/test/function/builtin/APPLYTester.java
+++ b/test/function/builtin/APPLYTester.java
@@ -13,21 +13,21 @@ public class APPLYTester {
     public void testApply() {
         String input = "(apply '+ '(1 2 3))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("6"));
+        assertSExpressionsMatch(parseString("6"), evaluateString(input));
     }
 
     @Test
     public void testApplyWithLambdaExpression() {
         String input = "(apply (lambda (x) (+ x 1)) '(25))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("26"));
+        assertSExpressionsMatch(parseString("26"), evaluateString(input));
     }
 
     @Test
     public void testApplyWithQuotedLambdaExpression() {
         String input = "(apply '(lambda (x) (+ x 1)) '(25))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("26"));
+        assertSExpressionsMatch(parseString("26"), evaluateString(input));
     }
 
     @Test
@@ -35,7 +35,7 @@ public class APPLYTester {
         String argumentList = "(+ (25 10))";
         Cons parsedArgumentList = (Cons) parseString(argumentList);
 
-        assertSExpressionsMatch(APPLY.apply(parsedArgumentList), parseString("35"));
+        assertSExpressionsMatch(parseString("35"), APPLY.apply(parsedArgumentList));
     }
 
     @Test(expected = RuntimeException.class)
diff --git a/test/function/builtin/EVALTester.java b/test/function/builtin/EVALTester.java
index def4bf4..e1f0e78 100644
--- a/test/function/builtin/EVALTester.java
+++ b/test/function/builtin/EVALTester.java
@@ -15,26 +15,26 @@ public class EVALTester {
     public void testEval() {
         String input = "(eval 9)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("9"));
+        assertSExpressionsMatch(parseString("9"), evaluateString(input));
     }
 
     @Test
     public void testEvalNil() {
         String input = "(eval ())";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("()"));
+        assertSExpressionsMatch(parseString("()"), evaluateString(input));
     }
 
     @Test
     public void testLookupSymbol() {
         String symbol = ":symbol";
-        assertSExpressionsMatch(EVAL.lookupSymbol(symbol), parseString(symbol));
+        assertSExpressionsMatch(parseString(symbol), EVAL.lookupSymbol(symbol));
     }
 
     @Test
     public void testLookupT() {
         String symbol = "T";
-        assertSExpressionsMatch(EVAL.lookupSymbol(symbol), parseString(symbol));
+        assertSExpressionsMatch(parseString(symbol), EVAL.lookupSymbol(symbol));
     }
 
     @Test
diff --git a/test/function/builtin/FUNCALLTester.java b/test/function/builtin/FUNCALLTester.java
index 71d4e06..f14bee7 100644
--- a/test/function/builtin/FUNCALLTester.java
+++ b/test/function/builtin/FUNCALLTester.java
@@ -12,7 +12,7 @@ public class FUNCALLTester {
     public void testFuncallWithNumbers() {
         String input = "(funcall '+ 1 2 3)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("6"));
+        assertSExpressionsMatch(parseString("6"), evaluateString(input));
     }
 
     @Test
@@ -21,7 +21,7 @@ public class FUNCALLTester {
         String input = "(funcall 'x 2 30)";
 
         evaluateString(defineUserFunction);
-        assertSExpressionsMatch(evaluateString(input), parseString("32"));
+        assertSExpressionsMatch(parseString("32"), evaluateString(input));
     }
 
     @Test(expected = TooFewArgumentsException.class)
diff --git a/test/function/builtin/LOADTester.java b/test/function/builtin/LOADTester.java
index 90c4d66..beee965 100644
--- a/test/function/builtin/LOADTester.java
+++ b/test/function/builtin/LOADTester.java
@@ -9,6 +9,7 @@ import org.junit.*;
 
 import environment.Environment;
 import function.ArgumentValidator.*;
+import sexpression.*;
 
 public class LOADTester {
 
@@ -32,7 +33,7 @@ public class LOADTester {
     public void loadGoodFile_ReturnsTAndPrintsNothing() {
         String input = "(load \"test/function/builtin/test-files/load-good.lisp\")";
 
-        assertSExpressionsMatch(parseString("T"), evaluateString(input));
+        assertSExpressionsMatch(Symbol.T, evaluateString(input));
         assertNothingPrinted();
     }
 
@@ -40,7 +41,7 @@ public class LOADTester {
     public void loadBadFile_ReturnsNilAndPrintsError() {
         String input = "(load \"test/function/builtin/test-files/load-bad.lisp\")";
 
-        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
+        assertSExpressionsMatch(Nil.getInstance(), evaluateString(input));
         assertPrinted("LOAD: expression begins with ')' - line 1, column 1\n");
     }
 
@@ -48,7 +49,7 @@ public class LOADTester {
     public void loadNonExistentFile_ReturnsNilAndPrintsError() {
         String input = "(load \"doesNotExist.lisp\")";
 
-        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
+        assertSExpressionsMatch(Nil.getInstance(), evaluateString(input));
         assertPrinted("LOAD: could not open 'doesNotExist.lisp'\n");
     }
 
diff --git a/test/function/builtin/cons/CARTester.java b/test/function/builtin/cons/CARTester.java
index 9a67c33..5d2d7fe 100644
--- a/test/function/builtin/cons/CARTester.java
+++ b/test/function/builtin/cons/CARTester.java
@@ -12,21 +12,21 @@ public class CARTester {
     public void testCarWithNil() {
         String input = "(car nil)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("()"));
+        assertSExpressionsMatch(parseString("()"), evaluateString(input));
     }
 
     @Test
     public void testCarWithList() {
         String input = "(car '(1 2 3))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("1"));
+        assertSExpressionsMatch(parseString("1"), evaluateString(input));
     }
 
     @Test
     public void testNestedCarWithList() {
         String input = "(car (car '((1 2) 3)))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("1"));
+        assertSExpressionsMatch(parseString("1"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/cons/CDRTester.java b/test/function/builtin/cons/CDRTester.java
index 394a01c..22b27dd 100644
--- a/test/function/builtin/cons/CDRTester.java
+++ b/test/function/builtin/cons/CDRTester.java
@@ -12,21 +12,21 @@ public class CDRTester {
     public void testCdrWithNil() {
         String input = "(cdr nil)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("()"));
+        assertSExpressionsMatch(parseString("()"), evaluateString(input));
     }
 
     @Test
     public void testCdrWithList() {
         String input = "(cdr '(1 2 3))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("(2 3)"));
+        assertSExpressionsMatch(parseString("(2 3)"), evaluateString(input));
     }
 
     @Test
     public void testNestedCdrWithList() {
         String input = "(cdr (cdr '(1 2 3)))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("(3)"));
+        assertSExpressionsMatch(parseString("(3)"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/cons/CONSTester.java b/test/function/builtin/cons/CONSTester.java
index 09526f9..98f06f2 100644
--- a/test/function/builtin/cons/CONSTester.java
+++ b/test/function/builtin/cons/CONSTester.java
@@ -13,27 +13,27 @@ public class CONSTester {
     public void testConsWithNilValues() {
         String input = "(cons () nil)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("(())"));
+        assertSExpressionsMatch(parseString("(())"), evaluateString(input));
     }
 
     @Test
     public void testConsWithTwoSymbols() {
         String input = "(cons 'a 'b)";
 
-        assertSExpressionsMatch(evaluateString(input), new Cons(new Symbol("A"), new Symbol("B")));
+        assertSExpressionsMatch(new Cons(new Symbol("A"), new Symbol("B")), evaluateString(input));
     }
 
     @Test
     public void testConsWithListAsCdr() {
         String input = "(cons 1 '(2 3))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("(1 2 3)"));
+        assertSExpressionsMatch(parseString("(1 2 3)"), evaluateString(input));
     }
     @Test
     public void testConsWithTwoLists() {
         String input = "(cons '(1 2) '(3 4))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("((1 2) 3 4)"));
+        assertSExpressionsMatch(parseString("((1 2) 3 4)"), evaluateString(input));
     }
 
 
@@ -41,7 +41,7 @@ public class CONSTester {
     public void testConsWithList() {
         String input = "(cons nil '(2 3))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("(nil 2 3)"));
+        assertSExpressionsMatch(parseString("(nil 2 3)"), evaluateString(input));
     }
 
     @Test(expected = TooManyArgumentsException.class)
diff --git a/test/function/builtin/cons/LENGTHTester.java b/test/function/builtin/cons/LENGTHTester.java
index 5786680..c42ed12 100644
--- a/test/function/builtin/cons/LENGTHTester.java
+++ b/test/function/builtin/cons/LENGTHTester.java
@@ -12,21 +12,21 @@ public class LENGTHTester {
     public void testLengthOfNil() {
         String input = "(length '())";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("0"));
+        assertSExpressionsMatch(parseString("0"), evaluateString(input));
     }
 
     @Test
     public void testLengthOfListOfOneElement() {
         String input = "(length '(1))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("1"));
+        assertSExpressionsMatch(parseString("1"), evaluateString(input));
     }
 
     @Test
     public void testLengthOfListOfManyElements() {
         String input = "(length '(1 2 3 4 5))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("5"));
+        assertSExpressionsMatch(parseString("5"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/cons/LISTTester.java b/test/function/builtin/cons/LISTTester.java
index 0c6b891..95e591c 100644
--- a/test/function/builtin/cons/LISTTester.java
+++ b/test/function/builtin/cons/LISTTester.java
@@ -10,47 +10,47 @@ public class LISTTester {
     public void testListWithNoArguments() {
         String input = "(list)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testListWithOneArgument() {
         String input = "(list 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("(1)"));
+        assertSExpressionsMatch(parseString("(1)"), evaluateString(input));
     }
 
     @Test
     public void testListWithTwoArguments() {
         String input = "(list 2 3)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("(2 3)"));
+        assertSExpressionsMatch(parseString("(2 3)"), evaluateString(input));
     }
 
     @Test
     public void testListWithManyArguments() {
         String input = "(list 'm 'a 'n 'y 'a 'r 'g 's)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("(m a n y a r g s)"));
+        assertSExpressionsMatch(parseString("(m a n y a r g s)"), evaluateString(input));
     }
 
     @Test
     public void testListWithOneListArgument() {
         String input = "(list '(1))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("((1))"));
+        assertSExpressionsMatch(parseString("((1))"), evaluateString(input));
     }
 
     @Test
     public void testListWithManyListArguments() {
         String input = "(list '(1) '(2 3) ())";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("((1) (2 3) ())"));
+        assertSExpressionsMatch(parseString("((1) (2 3) ())"), evaluateString(input));
     }
 
     @Test
     public void testMakeList() {
-        assertSExpressionsMatch(LIST.makeList(parseString("22")), parseString("(22)"));
+        assertSExpressionsMatch(parseString("(22)"), LIST.makeList(parseString("22")));
     }
 
 }
diff --git a/test/function/builtin/math/DIVIDETester.java b/test/function/builtin/math/DIVIDETester.java
index 682c24e..ebe778b 100644
--- a/test/function/builtin/math/DIVIDETester.java
+++ b/test/function/builtin/math/DIVIDETester.java
@@ -12,42 +12,42 @@ public class DIVIDETester {
     public void testDivideWithOne() {
         String input = "(/ 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("1"));
+        assertSExpressionsMatch(parseString("1"), evaluateString(input));
     }
 
     @Test
     public void testDivideWithTwo() {
         String input = "(/ 2)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("0"));
+        assertSExpressionsMatch(parseString("0"), evaluateString(input));
     }
 
     @Test
     public void testDivideTwoNumbers() {
         String input = "(/ 24 3)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("8"));
+        assertSExpressionsMatch(parseString("8"), evaluateString(input));
     }
 
     @Test
     public void testDivideSeveralNumbers() {
         String input = "(/ 256 2 2 8)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("8"));
+        assertSExpressionsMatch(parseString("8"), evaluateString(input));
     }
 
     @Test
     public void testDivideTwoNumbersWithRemainder() {
         String input = "(/ 9 2)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("4"));
+        assertSExpressionsMatch(parseString("4"), evaluateString(input));
     }
 
     @Test
     public void testDivideSeveralNumbersWithRemainder() {
         String input = "(/ 19 2 5)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("1"));
+        assertSExpressionsMatch(parseString("1"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/math/MINUSTester.java b/test/function/builtin/math/MINUSTester.java
index 87e7b89..0b5fe2e 100644
--- a/test/function/builtin/math/MINUSTester.java
+++ b/test/function/builtin/math/MINUSTester.java
@@ -13,28 +13,28 @@ public class MINUSTester {
     public void testMinusWithOneNumber() {
         String input = "(- 27)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("-27"));
+        assertSExpressionsMatch(new LispNumber("-27"), evaluateString(input));
     }
 
     @Test
     public void testMinusWithTwoNumbers() {
         String input = "(- 5 3)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("2"));
+        assertSExpressionsMatch(new LispNumber("2"), evaluateString(input));
     }
 
     @Test
     public void testMinusWithManyNumbers_PositiveResult() {
         String input = "(- 200 100 10 5)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("85"));
+        assertSExpressionsMatch(new LispNumber("85"), evaluateString(input));
     }
 
     @Test
     public void testMinusWithManyNumbers_NegativeResult() {
         String input = "(- 100 200 20 5)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("-125"));
+        assertSExpressionsMatch(new LispNumber("-125"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/math/MULTIPLYTester.java b/test/function/builtin/math/MULTIPLYTester.java
index e8a2ee0..766470a 100644
--- a/test/function/builtin/math/MULTIPLYTester.java
+++ b/test/function/builtin/math/MULTIPLYTester.java
@@ -13,35 +13,35 @@ public class MULTIPLYTester {
     public void testMultiplyWithNoArguments() {
         String input = "(*)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("1"));
+        assertSExpressionsMatch(new LispNumber("1"), evaluateString(input));
     }
 
     @Test
     public void testMultiplyWithOneNumber() {
         String input = "(* 8)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("8"));
+        assertSExpressionsMatch(new LispNumber("8"), evaluateString(input));
     }
 
     @Test
     public void testMultiplyWithTwoNumbers() {
         String input = "(* 5 3)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("15"));
+        assertSExpressionsMatch(new LispNumber("15"), evaluateString(input));
     }
 
     @Test
     public void testMultiplyWithManyNumbers_PositiveResult() {
         String input = "(* 2 3 5 1)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("30"));
+        assertSExpressionsMatch(new LispNumber("30"), evaluateString(input));
     }
 
     @Test
     public void testMultiplyWithManyNumbers_NegativeResult() {
         String input = "(* 3 (- 2) 10 2)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("-120"));
+        assertSExpressionsMatch(new LispNumber("-120"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/math/PLUSTester.java b/test/function/builtin/math/PLUSTester.java
index a23b793..e2c9260 100644
--- a/test/function/builtin/math/PLUSTester.java
+++ b/test/function/builtin/math/PLUSTester.java
@@ -13,35 +13,35 @@ public class PLUSTester {
     public void testPlusWithNoArguments() {
         String input = "(+)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("0"));
+        assertSExpressionsMatch(new LispNumber("0"), evaluateString(input));
     }
 
     @Test
     public void testPlusWithOneNumber() {
         String input = "(+ 27)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("27"));
+        assertSExpressionsMatch(new LispNumber("27"), evaluateString(input));
     }
 
     @Test
     public void testPlusWithTwoNumbers() {
         String input = "(+ 5 3)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("8"));
+        assertSExpressionsMatch(new LispNumber("8"), evaluateString(input));
     }
 
     @Test
     public void testPlusWithManyNumbers_PositiveResult() {
         String input = "(+ 200 100 10 5)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("315"));
+        assertSExpressionsMatch(new LispNumber("315"), evaluateString(input));
     }
 
     @Test
     public void testPlusWithManyNumbers_NegativeResult() {
         String input = "(+ 100 (- 200) 20 5)";
 
-        assertSExpressionsMatch(evaluateString(input), new LispNumber("-75"));
+        assertSExpressionsMatch(new LispNumber("-75"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/predicate/ATOMTester.java b/test/function/builtin/predicate/ATOMTester.java
index 08666bf..30fc55d 100644
--- a/test/function/builtin/predicate/ATOMTester.java
+++ b/test/function/builtin/predicate/ATOMTester.java
@@ -12,14 +12,14 @@ public class ATOMTester {
     public void testAtom_ReturnsTrue() {
         String input = "(atom 'a)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("T"));
+        assertSExpressionsMatch(parseString("T"), evaluateString(input));
     }
 
     @Test
     public void testAtom_ReturnsFalse() {
         String input = "(atom '(1 2 3))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("()"));
+        assertSExpressionsMatch(parseString("()"), evaluateString(input));
     }
 
     @Test(expected = TooManyArgumentsException.class)
diff --git a/test/function/builtin/predicate/EQTester.java b/test/function/builtin/predicate/EQTester.java
index c5e8660..02e5853 100644
--- a/test/function/builtin/predicate/EQTester.java
+++ b/test/function/builtin/predicate/EQTester.java
@@ -12,20 +12,20 @@ public class EQTester {
     public void testEqWithEqualAtoms() {
         String input = "(eq 1 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testEqWithUnequalAtoms() {
         String input = "(eq 1 2)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
     @Test
     public void testEqWithAtomAndList() {
         String input = "(eq 1 '(2))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
@@ -37,21 +37,21 @@ public class EQTester {
         evaluateString(initializeL1);
         evaluateString(initializeL2);
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testEqWithEqualLists() {
         String input = "(eq '(1 2) '(1 2))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testEqWithUnequalLists() {
         String input = "(eq '(1 2) '(3 4))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test(expected = TooManyArgumentsException.class)
diff --git a/test/function/builtin/predicate/EQUALSPTester.java b/test/function/builtin/predicate/EQUALSPTester.java
index 1372411..8941c35 100644
--- a/test/function/builtin/predicate/EQUALSPTester.java
+++ b/test/function/builtin/predicate/EQUALSPTester.java
@@ -12,35 +12,35 @@ public class EQUALSPTester {
     public void testEqualspWithOneNumber() {
         String input = "(= 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testEqualspWithEqualNumbers() {
         String input = "(= 1 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testEqualspWithNonEqualNumbers() {
         String input = "(= 1 2)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testEqualspWithManyEqualNumbers() {
         String input = "(= 4 4 4 4 4 4 4 4 4 4)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testEqualspWithManyNonEqualNumbers() {
         String input = "(= 4 4 4 4 5 4 4 4 4 4)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/predicate/EQUALTester.java b/test/function/builtin/predicate/EQUALTester.java
index a0681b8..a7276ee 100644
--- a/test/function/builtin/predicate/EQUALTester.java
+++ b/test/function/builtin/predicate/EQUALTester.java
@@ -12,49 +12,49 @@ public class EQUALTester {
     public void testEqualWithTwoEqualAtoms() {
         String input = "(equal 'a 'a)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testEqualWithTwoUnequalAtoms() {
         String input = "(equal 'a 'b)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testEqualWithAtomAndList() {
         String input = "(equal \"string\" '(m i k e))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testEqualWithListAndAtom() {
         String input = "(equal '(m i k e) \"string\")";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testEqualWithTwoEqualLists() {
         String input = "(equal '(1 2 3) '(1 2 3))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testEqualWithTwoUnequalLists() {
         String input = "(equal '(1 2 3) '(1 3 3))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testEqualWithTwoEqualNestedLists() {
         String input = "(equal '(1 ((2) 3)) '(1 ((2) 3)))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test(expected = TooManyArgumentsException.class)
diff --git a/test/function/builtin/predicate/GREATERPTester.java b/test/function/builtin/predicate/GREATERPTester.java
index 607743d..26ab718 100644
--- a/test/function/builtin/predicate/GREATERPTester.java
+++ b/test/function/builtin/predicate/GREATERPTester.java
@@ -12,35 +12,35 @@ public class GREATERPTester {
     public void testGreaterpWithOneNumber_ReturnsT() {
         String input = "(> 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testGreaterpWithTwoNumbers_ReturnsNil() {
         String input = "(> 1 2)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testGreaterpWithTwoNumbers_ReturnsT() {
         String input = "(> 3 2)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testGreaterpWithManyNumbers_ReturnsNil() {
         String input = "(> 4 3 2 5 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testGreaterpWithManyNumbers_ReturnsT() {
         String input = "(> 4 3 2 1 0)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/predicate/LESSPTester.java b/test/function/builtin/predicate/LESSPTester.java
index d4152fc..3dcc6aa 100644
--- a/test/function/builtin/predicate/LESSPTester.java
+++ b/test/function/builtin/predicate/LESSPTester.java
@@ -12,35 +12,35 @@ public class LESSPTester {
     public void testLesspWithOneNumber_ReturnsT() {
         String input = "(< 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testLesspWithTwoNumbers_ReturnsNil() {
         String input = "(< 2 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testLesspWithTwoNumbers_ReturnsT() {
         String input = "(< 2 3)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test
     public void testLesspWithManyNumbers_ReturnsNil() {
         String input = "(< 4 3 2 5 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testLesspWithManyNumbers_ReturnsT() {
         String input = "(< 0 1 2 3 4)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("t"));
+        assertSExpressionsMatch(parseString("t"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/predicate/LISTPTester.java b/test/function/builtin/predicate/LISTPTester.java
index e75e337..6f78838 100644
--- a/test/function/builtin/predicate/LISTPTester.java
+++ b/test/function/builtin/predicate/LISTPTester.java
@@ -12,14 +12,14 @@ public class LISTPTester {
     public void testListpWithList_ReturnsT() {
         String input = "(listp '(1))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("T"));
+        assertSExpressionsMatch(parseString("T"), evaluateString(input));
     }
 
     @Test
     public void testListWithNonList_ReturnsNil() {
         String input = "(listp 1)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("NIL"));
+        assertSExpressionsMatch(parseString("NIL"), evaluateString(input));
     }
 
     @Test(expected = TooFewArgumentsException.class)
diff --git a/test/function/builtin/predicate/NULLTester.java b/test/function/builtin/predicate/NULLTester.java
index 2ee7913..585525b 100644
--- a/test/function/builtin/predicate/NULLTester.java
+++ b/test/function/builtin/predicate/NULLTester.java
@@ -12,14 +12,14 @@ public class NULLTester {
     public void testNilIsNull() {
         String input = "(null ())";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("T"));
+        assertSExpressionsMatch(parseString("T"), evaluateString(input));
     }
 
     @Test
     public void testListIsNotNull() {
         String input = "(null '(1))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("NIL"));
+        assertSExpressionsMatch(parseString("NIL"), evaluateString(input));
     }
 
     @Test(expected = TooFewArgumentsException.class)
diff --git a/test/function/builtin/special/CONDTester.java b/test/function/builtin/special/CONDTester.java
index 5c764c0..acd7063 100644
--- a/test/function/builtin/special/CONDTester.java
+++ b/test/function/builtin/special/CONDTester.java
@@ -12,56 +12,56 @@ public class CONDTester {
     public void testCondWithNoArguments() {
         String input = "(cond)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test
     public void testCondWithTrue() {
         String input = "(cond (T))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("T"));
+        assertSExpressionsMatch(parseString("T"), evaluateString(input));
     }
 
     @Test
     public void testCondWithSingleExpression() {
         String input = "(cond (T \"true\"))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("\"true\""));
+        assertSExpressionsMatch(parseString("\"true\""), evaluateString(input));
     }
 
     @Test
     public void testCondWithMultipleExpressions() {
         String input = "(cond ((= 1 2) 2) ((= 1 2) 2) ((= 1 1) 3))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("3"));
+        assertSExpressionsMatch(parseString("3"), evaluateString(input));
     }
 
     @Test
     public void testCondWithMultipleConditionsMatching_ReturnFirstOne() {
         String input = "(cond ((= 1 1) 2) ((= 1 1) 3))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("2"));
+        assertSExpressionsMatch(parseString("2"), evaluateString(input));
     }
 
     @Test
     public void testCondWithMultipleConditionsMatching_OnlyEvaluatesFirstOne() {
         String input = "(cond ((= 1 1) 2) ((= 1 1) x))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("2"));
+        assertSExpressionsMatch(parseString("2"), evaluateString(input));
     }
 
     @Test
     public void testCondWithMultipleResultValues_OnlyReturnsLast() {
         String input = "(cond ((= 1 1) 2 3 4))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("4"));
+        assertSExpressionsMatch(parseString("4"), evaluateString(input));
     }
 
     @Test
     public void testCondWithNoConditionMatching_ReturnsNil() {
         String input = "(cond ((= 1 2) T) ((= 1 3) T))";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("nil"));
+        assertSExpressionsMatch(parseString("nil"), evaluateString(input));
     }
 
     @Test(expected = BadArgumentTypeException.class)
diff --git a/test/function/builtin/special/DEFUNTester.java b/test/function/builtin/special/DEFUNTester.java
index f580e01..4705fd2 100644
--- a/test/function/builtin/special/DEFUNTester.java
+++ b/test/function/builtin/special/DEFUNTester.java
@@ -12,8 +12,8 @@ public class DEFUNTester {
     public void testDefun() {
         String input = "(defun f () nil)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("f"));
-        assertSExpressionsMatch(evaluateString("(f)"), parseString("()"));
+        assertSExpressionsMatch(parseString("f"), evaluateString(input));
+        assertSExpressionsMatch(parseString("()"), evaluateString("(f)"));
     }
 
     @Test(expected = DottedArgumentListException.class)
diff --git a/test/function/builtin/special/QUOTETester.java b/test/function/builtin/special/QUOTETester.java
index fe042e3..4cf959d 100644
--- a/test/function/builtin/special/QUOTETester.java
+++ b/test/function/builtin/special/QUOTETester.java
@@ -12,14 +12,14 @@ public class QUOTETester {
     public void testQuoteSymbol() {
         String input = "'a";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("a"));
+        assertSExpressionsMatch(parseString("a"), evaluateString(input));
     }
 
     @Test
     public void testQuoteList() {
         String input = "'(l i s t)";
 
-        assertSExpressionsMatch(evaluateString(input), parseString("(l i s t)"));
+        assertSExpressionsMatch(parseString("(l i s t)"), evaluateString(input));
     }
 
     @Test(expected = TooFewArgumentsException.class)
diff --git a/test/function/builtin/special/SETFTester.java b/test/function/builtin/special/SETFTester.java
index aa55dab..ca0fde6 100644
--- a/test/function/builtin/special/SETFTester.java
+++ b/test/function/builtin/special/SETFTester.java
@@ -20,13 +20,13 @@ public class SETFTester {
     @Test
     public void testSetf() {
         evaluateString("(setf a 23)");
-        assertSExpressionsMatch(evaluateString("23"), evaluateString("a"));
+        assertSExpressionsMatch(new LispNumber("23"), evaluateString("a"));
     }
 
     @Test
     public void lookupDefinedSymbol() {
         evaluateString("(setf a 23)");
-        assertSExpressionsMatch(evaluateString("23"), SETF.lookupSymbolValue("A"));
+        assertSExpressionsMatch(new LispNumber("23"), SETF.lookupSymbolValue("A"));
     }
 
     @Test
@@ -42,7 +42,7 @@ public class SETFTester {
 
         evaluateString("(setf a 94)");
         SETF.setSymbolTable(global);
-        assertSExpressionsMatch(evaluateString("94"), evaluateString("a"));
+        assertSExpressionsMatch(new LispNumber("94"), evaluateString("a"));
     }
 
     @Test(expected = UndefinedSymbolException.class)
@@ -65,7 +65,7 @@ public class SETFTester {
 
         evaluateString("(setf a 94)");
         SETF.setSymbolTable(global);
-        assertSExpressionsMatch(evaluateString("94"), evaluateString("a"));
+        assertSExpressionsMatch(new LispNumber("94"), evaluateString("a"));
     }
 
     @Test(expected = BadArgumentTypeException.class)