diff --git a/src/main/kotlin/function/builtin/Apply.kt b/src/main/kotlin/function/builtin/Apply.kt
index 37ecd32..c830bb4 100644
--- a/src/main/kotlin/function/builtin/Apply.kt
+++ b/src/main/kotlin/function/builtin/Apply.kt
@@ -7,7 +7,7 @@ import function.builtin.Eval.Companion.applyFunction
 import function.builtin.Eval.Companion.lookupFunctionOrLambda
 import sexpression.Cons
 import sexpression.SExpression
-import table.FunctionTable
+import table.FunctionTable.lookupFunction
 
 @FunctionNames("APPLY")
 class Apply(name: String) : LispFunction() {
@@ -31,7 +31,7 @@ class Apply(name: String) : LispFunction() {
     companion object {
 
         fun apply(argumentList: Cons): SExpression {
-            return FunctionTable.lookupFunction("APPLY")!!.call(argumentList)
+            return lookupFunction("APPLY")!!.call(argumentList)
         }
     }
 }
diff --git a/src/main/kotlin/function/builtin/Eval.kt b/src/main/kotlin/function/builtin/Eval.kt
index 6b8233f..93aad4c 100644
--- a/src/main/kotlin/function/builtin/Eval.kt
+++ b/src/main/kotlin/function/builtin/Eval.kt
@@ -16,7 +16,7 @@ import sexpression.SExpression
 import sexpression.Symbol
 import sexpression.Symbol.Companion.T
 import table.ExecutionContext
-import table.FunctionTable
+import table.FunctionTable.lookupFunction
 
 @FunctionNames("EVAL")
 class Eval(name: String) : LispFunction() {
@@ -99,7 +99,7 @@ class Eval(name: String) : LispFunction() {
 
     companion object {
 
-        private fun lookupEval() = FunctionTable.lookupFunction("EVAL") as Eval
+        private fun lookupEval() = lookupFunction("EVAL") as Eval
 
         @JvmStatic
         fun eval(sExpression: SExpression): SExpression {
@@ -128,7 +128,7 @@ class Eval(name: String) : LispFunction() {
 
         @JvmStatic
         fun lookupFunctionOrLambda(functionExpression: SExpression): LispFunction {
-            val function = FunctionTable.lookupFunction(functionExpression.toString())
+            val function = lookupFunction(functionExpression.toString())
 
             return function ?: createLambdaFunction(functionExpression)
         }
diff --git a/src/main/kotlin/function/builtin/Set.kt b/src/main/kotlin/function/builtin/Set.kt
index 131e842..f14e2d7 100644
--- a/src/main/kotlin/function/builtin/Set.kt
+++ b/src/main/kotlin/function/builtin/Set.kt
@@ -7,7 +7,7 @@ import sexpression.Cons
 import sexpression.SExpression
 import sexpression.Symbol
 import table.ExecutionContext
-import table.FunctionTable
+import table.FunctionTable.lookupFunction
 import table.SymbolTable
 
 @FunctionNames("SET")
@@ -47,6 +47,6 @@ class Set(name: String) : LispFunction() {
     companion object {
 
         @JvmStatic
-        fun set(argumentList: Cons) = FunctionTable.lookupFunction("SET")!!.call(argumentList)
+        fun set(argumentList: Cons) = lookupFunction("SET")!!.call(argumentList)
     }
 }
diff --git a/src/main/kotlin/function/builtin/SymbolFunction.kt b/src/main/kotlin/function/builtin/SymbolFunction.kt
index 3b5688a..82cc631 100644
--- a/src/main/kotlin/function/builtin/SymbolFunction.kt
+++ b/src/main/kotlin/function/builtin/SymbolFunction.kt
@@ -9,7 +9,7 @@ import function.UserDefinedFunction
 import sexpression.Cons
 import sexpression.SExpression
 import sexpression.Symbol
-import table.FunctionTable
+import table.FunctionTable.lookupFunction
 
 @FunctionNames("SYMBOL-FUNCTION")
 class SymbolFunction(name: String) : LispFunction() {
@@ -23,7 +23,7 @@ class SymbolFunction(name: String) : LispFunction() {
         argumentValidator.validate(argumentList)
 
         val symbol = argumentList.first
-        val function = FunctionTable.lookupFunction(symbol.toString())
+        val function = lookupFunction(symbol.toString())
 
         if (function != null)
             return createRepresentation(symbol, function)
diff --git a/src/main/kotlin/function/builtin/cons/Append.kt b/src/main/kotlin/function/builtin/cons/Append.kt
index a5cfd53..1868c54 100644
--- a/src/main/kotlin/function/builtin/cons/Append.kt
+++ b/src/main/kotlin/function/builtin/cons/Append.kt
@@ -5,7 +5,7 @@ import function.FunctionNames
 import function.LispFunction
 import sexpression.Cons
 import sexpression.Nil
-import table.FunctionTable
+import table.FunctionTable.lookupFunction
 
 @FunctionNames("APPEND")
 class Append(name: String) : LispFunction() {
@@ -58,6 +58,6 @@ class Append(name: String) : LispFunction() {
             return lookupAppend().appendLists(firstList, secondList)
         }
 
-        private fun lookupAppend() = FunctionTable.lookupFunction("APPEND") as Append
+        private fun lookupAppend() = lookupFunction("APPEND") as Append
     }
 }
diff --git a/src/main/kotlin/function/builtin/cons/Length.kt b/src/main/kotlin/function/builtin/cons/Length.kt
index c21d050..79fc1b8 100644
--- a/src/main/kotlin/function/builtin/cons/Length.kt
+++ b/src/main/kotlin/function/builtin/cons/Length.kt
@@ -5,7 +5,6 @@ import function.FunctionNames
 import function.LispFunction
 import sexpression.Cons
 import sexpression.LispNumber
-import table.FunctionTable
 import table.FunctionTable.lookupFunction
 import java.math.BigInteger.ZERO