Refactor Node to refer other Nodes instead of Any

src/main/kotlin/dsl/ast/model/node/AtomAbstractNode.kt

@@ -2,12 +2,10 @@ package dsl.ast.model.node
 
 import dsl.token.model.entity.Token
 
-abstract class AtomAbstractNode(token: Token) : Node(1, token.position) {
-    val value: Any
-    get() = children[0]
-
-    init {
-        children[0] = token.value
+abstract class AtomAbstractNode(val token: Token) : Node(1, token.position) {
+    override fun pretty(prefix: String, last: Boolean, first: Boolean) {
+        println(prefix + (if (first) "" else if (last) "└─" else "├─") + this::class.simpleName + " " + position)
+        println(prefix + (if (last) "   " else "│  ") + "└ " + token)
     }
 }
 

src/main/kotlin/dsl/ast/model/node/BinaryOperatorAbstractNode.kt

@@ -1,13 +1,13 @@
 package dsl.ast.model.node
 
 abstract class BinaryOperatorAbstractNode(lhs: Node, operator: Node, rhs: Node) : Node(3, operator.position) {
-    val lhs: Any
+    val lhs: Node
     get() = children[0]
 
-    val operator: Any
+    val operator: Node
     get() = children[1]
 
-    val rhs: Any
+    val rhs: Node
     get() = children[2]
 
     init {

src/main/kotlin/dsl/ast/model/node/BlockNode.kt

@@ -1,7 +1,7 @@
 package dsl.ast.model.node
 
 class BlockNode(begin: Node, statements: List<Node>, end: Node) : Node(statements, begin.position) {
-    val statements: List<Any>
+    val statements: List<Node>
     get() = children
 
     init {

src/main/kotlin/dsl/ast/model/node/ConditionNode.kt

@@ -1,13 +1,13 @@
 package dsl.ast.model.node
 
 class ConditionNode(trueBranchToken: Node, condition: Node, trueBranch: Node, falseBranchToken: Node, falseBranch: Node) : Node(3, trueBranchToken.position) {
-    val condition: Any
+    val condition: Node
     get() = children[0]
 
-    val trueBranch: Any
+    val trueBranch: Node
     get() = children[1]
 
-    val falseBranch: Any
+    val falseBranch: Node
     get() = children[2]
 
     init {

src/main/kotlin/dsl/ast/model/node/Node.kt

@@ -3,20 +3,20 @@ package dsl.ast.model.node
 import dsl.token.model.entity.TokenPosition
 
 abstract class Node(numberOfChildren: Int, val position: TokenPosition) {
-    var children: MutableList<Any> = MutableList(numberOfChildren) { NONE }
+    var children: MutableList<Node> = MutableList(numberOfChildren) { NONE }
         protected set
 
-    constructor(children: List<Any>, position: TokenPosition) : this(children.size, position) {
+    constructor(children: List<Node>, position: TokenPosition) : this(children.size, position) {
         this.children = children.toMutableList()
     }
 
     operator fun get(index: Int) = children[index]
 
-    operator fun set(index: Int, value: Any) {
+    operator fun set(index: Int, value: Node) {
         children[index] = value
     }
 
-    fun pretty(prefix: String = "", last: Boolean = true, first: Boolean = true) {
+    open fun pretty(prefix: String = "", last: Boolean = true, first: Boolean = true) {
         var newPrefix = prefix
         var newLast = last
         val nodeName = this::class.simpleName ?: "<anonymous>"
@@ -25,11 +25,8 @@ abstract class Node(numberOfChildren: Int, val position: TokenPosition) {
         newPrefix += if (newLast) "   " else "│  "
         for ((index, child) in children.withIndex()) {
             newLast = index == children.size - 1
-            if (child is Node) {
-                child.pretty(newPrefix, newLast, false)
-            } else {
-                println(newPrefix + (if (newLast) "└ " else "├ ") + child)
-            }
+            child.pretty(newPrefix, newLast, false)
+            //println(newPrefix + (if (newLast) "└ " else "├ ") + child) // todo move to atom nodes
         }
     }
 

src/main/kotlin/dsl/ast/model/node/ReturnNode.kt

@@ -1,7 +1,7 @@
 package dsl.ast.model.node
 
 class ReturnNode(value: Node) : Node(1, value.position) {
-    val value: Any
+    val value: Node
     get() = children[0]
 
     init {

src/main/kotlin/dsl/ast/model/node/ThrowNode.kt

@@ -1,7 +1,7 @@
 package dsl.ast.model.node
 
 class ThrowNode(value: Node) : Node(1, value.position) {
-    val value: Any
+    val value: Node
         get() = children[0]
 
     init {

src/main/kotlin/dsl/ast/model/node/TokenNode.kt

@@ -2,11 +2,4 @@ package dsl.ast.model.node
 
 import dsl.token.model.entity.Token
 
-class TokenNode(token: Token) : Node(1, token.position) {
-    val token: Any
-    get() = children[0]
-
-    init {
-        children[0] = token
-    }
-}
+class TokenNode(token: Token) : AtomAbstractNode(token)

src/main/kotlin/dsl/ast/model/node/UnaryOperatorAbstractNode.kt

@@ -1,10 +1,10 @@
 package dsl.ast.model.node
 
 abstract class UnaryOperatorAbstractNode(operator: Node, operand: Node) : Node(2, operator.position) {
-    val operator: Any
+    val operator: Node
     get() = children[0]
 
-    val operand: Any
+    val operand: Node
     get() = children[1]
 
     init {

src/main/kotlin/dsl/ast/parser/AtomParser.kt

@@ -15,6 +15,7 @@ class AtomParser : Parser() {
         ) {
             it[1]
         }
+
         val literalParser = oneOf(
             listOf(
                 parenthesesParser,