remove unused attributes fields

node/argument.go

@@ -1,34 +1,23 @@
 package node
 
 type Argument struct {
-	attributes map[string]interface{}
 	position *Position
-	expr       Node
-	variadic   bool
+	Variadic bool
+	Expr     Node
 }
 
-func NewArgument(Expression Node, variadic bool) Node {
+func NewArgument(Expression Node, Variadic bool) Node {
 	return &Argument{
-		map[string]interface{}{
-			"variadic": variadic,
-		},
 		nil,
+		Variadic,
 		Expression,
-		variadic,
 	}
 }
 
 func (n Argument) Attributes() map[string]interface{} {
-	return n.attributes
-}
-
-func (n Argument) Attribute(Key string) interface{} {
-	return n.attributes[Key]
-}
-
-func (n Argument) SetAttribute(Key string, Value interface{}) Node {
-	n.attributes[Key] = Value
-	return n
+	return map[string]interface{}{
+		"Variadic": n.Variadic,
+	}
 }
 
 func (n Argument) Position() *Position {
@@ -45,9 +34,9 @@ func (n Argument) Walk(v Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/array.go

@@ -5,21 +5,19 @@ import (
 )
 
 type Array struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Items    []node.Node
 }
 
 func NewArray(Items []node.Node) node.Node {
 	return &Array{
-		map[string]interface{}{},
 		nil,
 		Items,
 	}
 }
 
 func (n Array) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Array) Position() *node.Position {

node/expr/array_dim_fetch.go

@@ -5,7 +5,6 @@ import (
 )
 
 type ArrayDimFetch struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Variable node.Node
 	Dim      node.Node
@@ -13,7 +12,6 @@ type ArrayDimFetch struct {
 
 func NewArrayDimFetch(Variable node.Node, Dim node.Node) node.Node {
 	return &ArrayDimFetch{
-		map[string]interface{}{},
 		nil,
 		Variable,
 		Dim,
@@ -21,7 +19,7 @@ func NewArrayDimFetch(Variable node.Node, Dim node.Node) node.Node {
 }
 
 func (n ArrayDimFetch) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ArrayDimFetch) Position() *node.Position {

node/expr/array_item.go

@@ -5,25 +5,25 @@ import (
 )
 
 type ArrayItem struct {
-	attributes map[string]interface{}
 	position *node.Position
+	ByRef    bool
 	Key      node.Node
 	Val      node.Node
 }
 
-func NewArrayItem(Key node.Node, Val node.Node, byRef bool) node.Node {
+func NewArrayItem(Key node.Node, Val node.Node, ByRef bool) node.Node {
 	return &ArrayItem{
-		map[string]interface{}{
-			"byRef": byRef,
-		},
 		nil,
+		ByRef,
 		Key,
 		Val,
 	}
 }
 
 func (n ArrayItem) Attributes() map[string]interface{} {
-	return n.attributes
+	return map[string]interface{}{
+		"ByRef": n.ByRef,
+	}
 }
 
 func (n ArrayItem) Position() *node.Position {

node/expr/assign_op/assign.go

@@ -11,7 +11,6 @@ type Assign struct {
 func NewAssign(Variable node.Node, Expression node.Node) node.Node {
 	return &Assign{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewAssign(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Assign) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Assign) Position() *node.Position {

node/expr/assign_op/assign_op.go

@@ -5,7 +5,6 @@ import (
 )
 
 type AssignOp struct {
-	attributes map[string]interface{}
 	position   *node.Position
 	Variable   node.Node
 	Expression node.Node

node/expr/assign_op/assign_ref.go

@@ -11,7 +11,6 @@ type AssignRef struct {
 func NewAssignRef(Variable node.Node, Expression node.Node) node.Node {
 	return &AssignRef{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewAssignRef(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n AssignRef) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n AssignRef) Position() *node.Position {

node/expr/assign_op/bitwise_and.go

@@ -11,7 +11,6 @@ type BitwiseAnd struct {
 func NewBitwiseAnd(Variable node.Node, Expression node.Node) node.Node {
 	return &BitwiseAnd{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewBitwiseAnd(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n BitwiseAnd) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n BitwiseAnd) Position() *node.Position {

node/expr/assign_op/bitwise_or.go

@@ -11,7 +11,6 @@ type BitwiseOr struct {
 func NewBitwiseOr(Variable node.Node, Expression node.Node) node.Node {
 	return &BitwiseOr{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewBitwiseOr(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n BitwiseOr) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n BitwiseOr) Position() *node.Position {

node/expr/assign_op/bitwise_xor.go

@@ -11,7 +11,6 @@ type BitwiseXor struct {
 func NewBitwiseXor(Variable node.Node, Expression node.Node) node.Node {
 	return &BitwiseXor{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewBitwiseXor(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n BitwiseXor) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n BitwiseXor) Position() *node.Position {

node/expr/assign_op/concat.go

@@ -11,7 +11,6 @@ type Concat struct {
 func NewConcat(Variable node.Node, Expression node.Node) node.Node {
 	return &Concat{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewConcat(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Concat) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Concat) Position() *node.Position {

node/expr/assign_op/div.go

@@ -11,7 +11,6 @@ type Div struct {
 func NewDiv(Variable node.Node, Expression node.Node) node.Node {
 	return &Div{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewDiv(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Div) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Div) Position() *node.Position {

node/expr/assign_op/minus.go

@@ -11,7 +11,6 @@ type Minus struct {
 func NewMinus(Variable node.Node, Expression node.Node) node.Node {
 	return &Minus{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewMinus(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Minus) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Minus) Position() *node.Position {

node/expr/assign_op/mod.go

@@ -11,7 +11,6 @@ type Mod struct {
 func NewMod(Variable node.Node, Expression node.Node) node.Node {
 	return &Mod{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewMod(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Mod) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Mod) Position() *node.Position {

node/expr/assign_op/mul.go

@@ -11,7 +11,6 @@ type Mul struct {
 func NewMul(Variable node.Node, Expression node.Node) node.Node {
 	return &Mul{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewMul(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Mul) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Mul) Position() *node.Position {

node/expr/assign_op/plus.go

@@ -11,7 +11,6 @@ type Plus struct {
 func NewPlus(Variable node.Node, Expression node.Node) node.Node {
 	return &Plus{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewPlus(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Plus) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Plus) Position() *node.Position {

node/expr/assign_op/pow.go

@@ -11,7 +11,6 @@ type Pow struct {
 func NewPow(Variable node.Node, Expression node.Node) node.Node {
 	return &Pow{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewPow(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Pow) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Pow) Position() *node.Position {

node/expr/assign_op/shift_left.go

@@ -11,7 +11,6 @@ type ShiftLeft struct {
 func NewShiftLeft(Variable node.Node, Expression node.Node) node.Node {
 	return &ShiftLeft{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewShiftLeft(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n ShiftLeft) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ShiftLeft) Position() *node.Position {

node/expr/assign_op/shift_right.go

@@ -11,7 +11,6 @@ type ShiftRight struct {
 func NewShiftRight(Variable node.Node, Expression node.Node) node.Node {
 	return &ShiftRight{
 		AssignOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewShiftRight(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n ShiftRight) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ShiftRight) Position() *node.Position {

node/expr/binary_op/binary_op.go

@@ -5,7 +5,6 @@ import (
 )
 
 type BinaryOp struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Left     node.Node
 	Right    node.Node

node/expr/binary_op/bitwise_and.go

@@ -11,7 +11,6 @@ type BitwiseAnd struct {
 func NewBitwiseAnd(Variable node.Node, Expression node.Node) node.Node {
 	return &BitwiseAnd{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewBitwiseAnd(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n BitwiseAnd) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n BitwiseAnd) Position() *node.Position {

node/expr/binary_op/bitwise_or.go

@@ -11,7 +11,6 @@ type BitwiseOr struct {
 func NewBitwiseOr(Variable node.Node, Expression node.Node) node.Node {
 	return &BitwiseOr{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewBitwiseOr(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n BitwiseOr) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n BitwiseOr) Position() *node.Position {

node/expr/binary_op/bitwise_xor.go

@@ -11,7 +11,6 @@ type BitwiseXor struct {
 func NewBitwiseXor(Variable node.Node, Expression node.Node) node.Node {
 	return &BitwiseXor{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewBitwiseXor(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n BitwiseXor) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n BitwiseXor) Position() *node.Position {

node/expr/binary_op/boolean_and.go

@@ -11,7 +11,6 @@ type BooleanAnd struct {
 func NewBooleanAnd(Variable node.Node, Expression node.Node) node.Node {
 	return &BooleanAnd{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewBooleanAnd(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n BooleanAnd) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n BooleanAnd) Position() *node.Position {

node/expr/binary_op/boolean_or.go

@@ -11,7 +11,6 @@ type BooleanOr struct {
 func NewBooleanOr(Variable node.Node, Expression node.Node) node.Node {
 	return &BooleanOr{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewBooleanOr(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n BooleanOr) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n BooleanOr) Position() *node.Position {

node/expr/binary_op/coalesce.go

@@ -11,7 +11,6 @@ type Coalesce struct {
 func NewCoalesce(Variable node.Node, Expression node.Node) node.Node {
 	return &Coalesce{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewCoalesce(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Coalesce) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Coalesce) Position() *node.Position {

node/expr/binary_op/concat.go

@@ -11,7 +11,6 @@ type Concat struct {
 func NewConcat(Variable node.Node, Expression node.Node) node.Node {
 	return &Concat{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewConcat(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Concat) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Concat) Position() *node.Position {

node/expr/binary_op/div.go

@@ -11,7 +11,6 @@ type Div struct {
 func NewDiv(Variable node.Node, Expression node.Node) node.Node {
 	return &Div{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewDiv(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Div) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Div) Position() *node.Position {

node/expr/binary_op/equal.go

@@ -11,7 +11,6 @@ type Equal struct {
 func NewEqual(Variable node.Node, Expression node.Node) node.Node {
 	return &Equal{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewEqual(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Equal) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Equal) Position() *node.Position {

node/expr/binary_op/greater.go

@@ -11,7 +11,6 @@ type Greater struct {
 func NewGreater(Variable node.Node, Expression node.Node) node.Node {
 	return &Greater{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewGreater(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Greater) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Greater) Position() *node.Position {

node/expr/binary_op/greater_or_equal.go

@@ -11,7 +11,6 @@ type GreaterOrEqual struct {
 func NewGreaterOrEqual(Variable node.Node, Expression node.Node) node.Node {
 	return &GreaterOrEqual{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewGreaterOrEqual(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n GreaterOrEqual) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n GreaterOrEqual) Position() *node.Position {

node/expr/binary_op/identical.go

@@ -11,7 +11,6 @@ type Identical struct {
 func NewIdentical(Variable node.Node, Expression node.Node) node.Node {
 	return &Identical{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewIdentical(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Identical) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Identical) Position() *node.Position {

node/expr/binary_op/logical_and.go

@@ -11,7 +11,6 @@ type LogicalAnd struct {
 func NewLogicalAnd(Variable node.Node, Expression node.Node) node.Node {
 	return &LogicalAnd{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewLogicalAnd(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n LogicalAnd) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n LogicalAnd) Position() *node.Position {

node/expr/binary_op/logical_or.go

@@ -11,7 +11,6 @@ type LogicalOr struct {
 func NewLogicalOr(Variable node.Node, Expression node.Node) node.Node {
 	return &LogicalOr{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewLogicalOr(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n LogicalOr) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n LogicalOr) Position() *node.Position {

node/expr/binary_op/logical_xor.go

@@ -11,7 +11,6 @@ type LogicalXor struct {
 func NewLogicalXor(Variable node.Node, Expression node.Node) node.Node {
 	return &LogicalXor{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewLogicalXor(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n LogicalXor) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n LogicalXor) Position() *node.Position {

node/expr/binary_op/minus.go

@@ -11,7 +11,6 @@ type Minus struct {
 func NewMinus(Variable node.Node, Expression node.Node) node.Node {
 	return &Minus{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewMinus(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Minus) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Minus) Position() *node.Position {

node/expr/binary_op/mod.go

@@ -11,7 +11,6 @@ type Mod struct {
 func NewMod(Variable node.Node, Expression node.Node) node.Node {
 	return &Mod{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewMod(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Mod) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Mod) Position() *node.Position {

node/expr/binary_op/mul.go

@@ -11,7 +11,6 @@ type Mul struct {
 func NewMul(Variable node.Node, Expression node.Node) node.Node {
 	return &Mul{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewMul(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Mul) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Mul) Position() *node.Position {

node/expr/binary_op/not_equal.go

@@ -11,7 +11,6 @@ type NotEqual struct {
 func NewNotEqual(Variable node.Node, Expression node.Node) node.Node {
 	return &NotEqual{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewNotEqual(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n NotEqual) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n NotEqual) Position() *node.Position {

node/expr/binary_op/not_identical.go

@@ -11,7 +11,6 @@ type NotIdentical struct {
 func NewNotIdentical(Variable node.Node, Expression node.Node) node.Node {
 	return &NotIdentical{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewNotIdentical(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n NotIdentical) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n NotIdentical) Position() *node.Position {

node/expr/binary_op/plus.go

@@ -11,7 +11,6 @@ type Plus struct {
 func NewPlus(Variable node.Node, Expression node.Node) node.Node {
 	return &Plus{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewPlus(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Plus) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Plus) Position() *node.Position {

node/expr/binary_op/pow.go

@@ -11,7 +11,6 @@ type Pow struct {
 func NewPow(Variable node.Node, Expression node.Node) node.Node {
 	return &Pow{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewPow(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Pow) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Pow) Position() *node.Position {

node/expr/binary_op/shift_left.go

@@ -11,7 +11,6 @@ type ShiftLeft struct {
 func NewShiftLeft(Variable node.Node, Expression node.Node) node.Node {
 	return &ShiftLeft{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewShiftLeft(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n ShiftLeft) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ShiftLeft) Position() *node.Position {

node/expr/binary_op/shift_right.go

@@ -11,7 +11,6 @@ type ShiftRight struct {
 func NewShiftRight(Variable node.Node, Expression node.Node) node.Node {
 	return &ShiftRight{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewShiftRight(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n ShiftRight) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ShiftRight) Position() *node.Position {

node/expr/binary_op/smaller.go

@@ -11,7 +11,6 @@ type Smaller struct {
 func NewSmaller(Variable node.Node, Expression node.Node) node.Node {
 	return &Smaller{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewSmaller(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Smaller) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Smaller) Position() *node.Position {

node/expr/binary_op/smaller_or_equal.go

@@ -11,7 +11,6 @@ type SmallerOrEqual struct {
 func NewSmallerOrEqual(Variable node.Node, Expression node.Node) node.Node {
 	return &SmallerOrEqual{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewSmallerOrEqual(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n SmallerOrEqual) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n SmallerOrEqual) Position() *node.Position {

node/expr/binary_op/spaceship.go

@@ -11,7 +11,6 @@ type Spaceship struct {
 func NewSpaceship(Variable node.Node, Expression node.Node) node.Node {
 	return &Spaceship{
 		BinaryOp{
-			map[string]interface{}{},
 			nil,
 			Variable,
 			Expression,
@@ -20,7 +19,7 @@ func NewSpaceship(Variable node.Node, Expression node.Node) node.Node {
 }
 
 func (n Spaceship) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Spaceship) Position() *node.Position {

node/expr/bitwise_not.go

@@ -5,21 +5,19 @@ import (
 )
 
 type BitwiseNot struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewBitwiseNot(Expression node.Node) node.Node {
 	return &BitwiseNot{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n BitwiseNot) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n BitwiseNot) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n BitwiseNot) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/boolean_not.go

@@ -5,21 +5,19 @@ import (
 )
 
 type BooleanNot struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewBooleanNot(Expression node.Node) node.Node {
 	return &BooleanNot{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n BooleanNot) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n BooleanNot) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n BooleanNot) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/cast/cast.go

@@ -5,7 +5,6 @@ import (
 )
 
 type Cast struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }

node/expr/cast/cast_array.go

@@ -8,18 +8,17 @@ type CastArray struct {
 	Cast
 }
 
-func NewCastArray(expr node.Node) node.Node {
+func NewCastArray(Expr node.Node) node.Node {
 	return &CastArray{
 		Cast{
-			map[string]interface{}{},
 			nil,
-			expr,
+			Expr,
 		},
 	}
 }
 
 func (n CastArray) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n CastArray) Position() *node.Position {
@@ -36,9 +35,9 @@ func (n CastArray) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/cast/cast_bool.go

@@ -8,18 +8,17 @@ type CastBool struct {
 	Cast
 }
 
-func NewCastBool(expr node.Node) node.Node {
+func NewCastBool(Expr node.Node) node.Node {
 	return &CastBool{
 		Cast{
-			map[string]interface{}{},
 			nil,
-			expr,
+			Expr,
 		},
 	}
 }
 
 func (n CastBool) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n CastBool) Position() *node.Position {
@@ -36,9 +35,9 @@ func (n CastBool) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/cast/cast_double.go

@@ -8,18 +8,17 @@ type CastDouble struct {
 	Cast
 }
 
-func NewCastDouble(expr node.Node) node.Node {
+func NewCastDouble(Expr node.Node) node.Node {
 	return &CastDouble{
 		Cast{
-			map[string]interface{}{},
 			nil,
-			expr,
+			Expr,
 		},
 	}
 }
 
 func (n CastDouble) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n CastDouble) Position() *node.Position {
@@ -36,9 +35,9 @@ func (n CastDouble) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/cast/cast_int.go

@@ -8,18 +8,17 @@ type CastInt struct {
 	Cast
 }
 
-func NewCastInt(expr node.Node) node.Node {
+func NewCastInt(Expr node.Node) node.Node {
 	return &CastInt{
 		Cast{
-			map[string]interface{}{},
 			nil,
-			expr,
+			Expr,
 		},
 	}
 }
 
 func (n CastInt) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n CastInt) Position() *node.Position {
@@ -36,9 +35,9 @@ func (n CastInt) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/cast/cast_object.go

@@ -8,18 +8,17 @@ type CastObject struct {
 	Cast
 }
 
-func NewCastObject(expr node.Node) node.Node {
+func NewCastObject(Expr node.Node) node.Node {
 	return &CastObject{
 		Cast{
-			map[string]interface{}{},
 			nil,
-			expr,
+			Expr,
 		},
 	}
 }
 
 func (n CastObject) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n CastObject) Position() *node.Position {
@@ -36,9 +35,9 @@ func (n CastObject) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/cast/cast_string.go

@@ -8,18 +8,17 @@ type CastString struct {
 	Cast
 }
 
-func NewCastString(expr node.Node) node.Node {
+func NewCastString(Expr node.Node) node.Node {
 	return &CastString{
 		Cast{
-			map[string]interface{}{},
 			nil,
-			expr,
+			Expr,
 		},
 	}
 }
 
 func (n CastString) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n CastString) Position() *node.Position {
@@ -36,9 +35,9 @@ func (n CastString) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/cast/cast_unset.go

@@ -8,18 +8,17 @@ type CastUnset struct {
 	Cast
 }
 
-func NewCastUnset(expr node.Node) node.Node {
+func NewCastUnset(Expr node.Node) node.Node {
 	return &CastUnset{
 		Cast{
-			map[string]interface{}{},
 			nil,
-			expr,
+			Expr,
 		},
 	}
 }
 
 func (n CastUnset) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n CastUnset) Position() *node.Position {
@@ -36,9 +35,9 @@ func (n CastUnset) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/class_const_fetch.go

@@ -5,7 +5,6 @@ import (
 )
 
 type ClassConstFetch struct {
-	attributes   map[string]interface{}
 	position     *node.Position
 	Class        node.Node
 	ConstantName node.Node
@@ -13,7 +12,6 @@ type ClassConstFetch struct {
 
 func NewClassConstFetch(Class node.Node, ConstantName node.Node) node.Node {
 	return &ClassConstFetch{
-		map[string]interface{}{},
 		nil,
 		Class,
 		ConstantName,
@@ -21,7 +19,7 @@ func NewClassConstFetch(Class node.Node, ConstantName node.Node) node.Node {
 }
 
 func (n ClassConstFetch) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ClassConstFetch) Position() *node.Position {

node/expr/clone.go

@@ -5,21 +5,19 @@ import (
 )
 
 type Clone struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewClone(Expression node.Node) node.Node {
 	return &Clone{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n Clone) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Clone) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n Clone) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/closure.go

@@ -5,22 +5,22 @@ import (
 )
 
 type Closure struct {
-	attributes map[string]interface{}
 	position      *node.Position
+	ReturnsRef    bool
+	Static        bool
+	PhpDocComment string
 	Params        []node.Node
 	Uses          []node.Node
 	ReturnType    node.Node
 	Stmts         []node.Node
 }
 
-func NewClosure(Params []node.Node, Uses []node.Node, ReturnType node.Node, Stmts []node.Node, isStatic bool, isReturnRef bool, phpDocComment string) node.Node {
+func NewClosure(Params []node.Node, Uses []node.Node, ReturnType node.Node, Stmts []node.Node, Static bool, ReturnsRef bool, PhpDocComment string) node.Node {
 	return &Closure{
-		map[string]interface{}{
-			"isReturnRef":   isReturnRef,
-			"isStatic":      isStatic,
-			"phpDocComment": phpDocComment,
-		},
 		nil,
+		ReturnsRef,
+		Static,
+		PhpDocComment,
 		Params,
 		Uses,
 		ReturnType,
@@ -29,7 +29,11 @@ func NewClosure(Params []node.Node, Uses []node.Node, ReturnType node.Node, Stmt
 }
 
 func (n Closure) Attributes() map[string]interface{} {
-	return n.attributes
+	return map[string]interface{}{
+		"ReturnsRef":    n.ReturnsRef,
+		"Static":        n.Static,
+		"PhpDocComment": n.PhpDocComment,
+	}
 }
 
 func (n Closure) Position() *node.Position {

node/expr/closure_use.go

@@ -5,23 +5,23 @@ import (
 )
 
 type ClusureUse struct {
-	attributes map[string]interface{}
 	position *node.Position
+	ByRef    bool
 	Variable node.Node
 }
 
-func NewClusureUse(Variable node.Node, byRef bool) node.Node {
+func NewClusureUse(Variable node.Node, ByRef bool) node.Node {
 	return &ClusureUse{
-		map[string]interface{}{
-			"byRef": byRef,
-		},
 		nil,
+		ByRef,
 		Variable,
 	}
 }
 
 func (n ClusureUse) Attributes() map[string]interface{} {
-	return n.attributes
+	return map[string]interface{}{
+		"ByRef": n.ByRef,
+	}
 }
 
 func (n ClusureUse) Position() *node.Position {

node/expr/const_fetch.go

@@ -5,21 +5,19 @@ import (
 )
 
 type ConstFetch struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Constant node.Node
 }
 
 func NewConstFetch(Constant node.Node) node.Node {
 	return &ConstFetch{
-		map[string]interface{}{},
 		nil,
 		Constant,
 	}
 }
 
 func (n ConstFetch) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ConstFetch) Position() *node.Position {

node/expr/empty.go

@@ -5,21 +5,19 @@ import (
 )
 
 type Empty struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewEmpty(Expression node.Node) node.Node {
 	return &Empty{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n Empty) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Empty) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n Empty) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/error_suppress.go

@@ -5,21 +5,19 @@ import (
 )
 
 type ErrorSuppress struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewErrorSuppress(Expression node.Node) node.Node {
 	return &ErrorSuppress{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n ErrorSuppress) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ErrorSuppress) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n ErrorSuppress) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/eval.go

@@ -5,21 +5,19 @@ import (
 )
 
 type Eval struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewEval(Expression node.Node) node.Node {
 	return &Eval{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n Eval) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Eval) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n Eval) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/exit.go

@@ -5,23 +5,23 @@ import (
 )
 
 type Exit struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
+	IsDie    bool
 }
 
-func NewExit(expr node.Node, isDie bool) node.Node {
+func NewExit(Expr node.Node, IsDie bool) node.Node {
 	return &Exit{
-		map[string]interface{}{
-			"isDie": isDie,
-		},
 		nil,
-		expr,
+		Expr,
+		IsDie,
 	}
 }
 
 func (n Exit) Attributes() map[string]interface{} {
-	return n.attributes
+	return map[string]interface{}{
+		"IsDie": n.IsDie,
+	}
 }
 
 func (n Exit) Position() *node.Position {
@@ -38,9 +38,9 @@ func (n Exit) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/function_call.go

@@ -5,7 +5,6 @@ import (
 )
 
 type FunctionCall struct {
-	attributes map[string]interface{}
 	position  *node.Position
 	Function  node.Node
 	Arguments []node.Node
@@ -13,7 +12,6 @@ type FunctionCall struct {
 
 func NewFunctionCall(Function node.Node, Arguments []node.Node) node.Node {
 	return &FunctionCall{
-		map[string]interface{}{},
 		nil,
 		Function,
 		Arguments,
@@ -21,7 +19,7 @@ func NewFunctionCall(Function node.Node, Arguments []node.Node) node.Node {
 }
 
 func (n FunctionCall) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n FunctionCall) Position() *node.Position {

node/expr/include.go

@@ -5,21 +5,19 @@ import (
 )
 
 type Include struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewInclude(Expression node.Node) node.Node {
 	return &Include{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n Include) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Include) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n Include) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/include_once.go

@@ -5,21 +5,19 @@ import (
 )
 
 type IncludeOnce struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewIncludeOnce(Expression node.Node) node.Node {
 	return &IncludeOnce{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n IncludeOnce) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n IncludeOnce) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n IncludeOnce) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/instance_of.go

@@ -5,23 +5,21 @@ import (
 )
 
 type InstanceOf struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 	Class    node.Node
 }
 
-func NewInstanceOf(expr node.Node, Class node.Node) node.Node {
+func NewInstanceOf(Expr node.Node, Class node.Node) node.Node {
 	return &InstanceOf{
-		map[string]interface{}{},
 		nil,
-		expr,
+		Expr,
 		Class,
 	}
 }
 
 func (n InstanceOf) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n InstanceOf) Position() *node.Position {
@@ -38,9 +36,9 @@ func (n InstanceOf) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	if n.Class != nil {

node/expr/isset.go

@@ -5,21 +5,19 @@ import (
 )
 
 type Isset struct {
-	attributes map[string]interface{}
 	position  *node.Position
 	Variables []node.Node
 }
 
 func NewIsset(Variables []node.Node) node.Node {
 	return &Isset{
-		map[string]interface{}{},
 		nil,
 		Variables,
 	}
 }
 
 func (n Isset) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Isset) Position() *node.Position {

node/expr/list.go

@@ -5,21 +5,19 @@ import (
 )
 
 type List struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Items    []node.Node
 }
 
 func NewList(Items []node.Node) node.Node {
 	return &List{
-		map[string]interface{}{},
 		nil,
 		Items,
 	}
 }
 
 func (n List) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n List) Position() *node.Position {

node/expr/method_call.go

@@ -5,7 +5,6 @@ import (
 )
 
 type MethodCall struct {
-	attributes map[string]interface{}
 	position  *node.Position
 	Variable  node.Node
 	Method    node.Node
@@ -14,7 +13,6 @@ type MethodCall struct {
 
 func NewMethodCall(Variable node.Node, Method node.Node, Arguments []node.Node) node.Node {
 	return &MethodCall{
-		map[string]interface{}{},
 		nil,
 		Variable,
 		Method,
@@ -23,7 +21,7 @@ func NewMethodCall(Variable node.Node, Method node.Node, Arguments []node.Node)
 }
 
 func (n MethodCall) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n MethodCall) Position() *node.Position {

node/expr/new.go

@@ -5,7 +5,6 @@ import (
 )
 
 type New struct {
-	attributes map[string]interface{}
 	position  *node.Position
 	Class     node.Node
 	Arguments []node.Node
@@ -13,7 +12,6 @@ type New struct {
 
 func NewNew(Class node.Node, Arguments []node.Node) node.Node {
 	return &New{
-		map[string]interface{}{},
 		nil,
 		Class,
 		Arguments,
@@ -21,7 +19,7 @@ func NewNew(Class node.Node, Arguments []node.Node) node.Node {
 }
 
 func (n New) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n New) Position() *node.Position {

node/expr/post_dec.go

@@ -5,21 +5,19 @@ import (
 )
 
 type PostDec struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Variable node.Node
 }
 
 func NewPostDec(Variable node.Node) node.Node {
 	return &PostDec{
-		map[string]interface{}{},
 		nil,
 		Variable,
 	}
 }
 
 func (n PostDec) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n PostDec) Position() *node.Position {

node/expr/post_inc.go

@@ -5,21 +5,19 @@ import (
 )
 
 type PostInc struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Variable node.Node
 }
 
 func NewPostInc(Variable node.Node) node.Node {
 	return &PostInc{
-		map[string]interface{}{},
 		nil,
 		Variable,
 	}
 }
 
 func (n PostInc) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n PostInc) Position() *node.Position {

node/expr/pre_dec.go

@@ -5,21 +5,19 @@ import (
 )
 
 type PreDec struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Variable node.Node
 }
 
 func NewPreDec(Variable node.Node) node.Node {
 	return &PreDec{
-		map[string]interface{}{},
 		nil,
 		Variable,
 	}
 }
 
 func (n PreDec) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n PreDec) Position() *node.Position {

node/expr/pre_inc.go

@@ -5,21 +5,19 @@ import (
 )
 
 type PreInc struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Variable node.Node
 }
 
 func NewPreInc(Variable node.Node) node.Node {
 	return &PreInc{
-		map[string]interface{}{},
 		nil,
 		Variable,
 	}
 }
 
 func (n PreInc) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n PreInc) Position() *node.Position {

node/expr/print.go

@@ -5,21 +5,19 @@ import (
 )
 
 type Print struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewPrint(Expression node.Node) node.Node {
 	return &Print{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n Print) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Print) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n Print) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/property_fetch.go

@@ -5,7 +5,6 @@ import (
 )
 
 type PropertyFetch struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Variable node.Node
 	Property node.Node
@@ -13,7 +12,6 @@ type PropertyFetch struct {
 
 func NewPropertyFetch(Variable node.Node, Property node.Node) node.Node {
 	return &PropertyFetch{
-		map[string]interface{}{},
 		nil,
 		Variable,
 		Property,
@@ -21,7 +19,7 @@ func NewPropertyFetch(Variable node.Node, Property node.Node) node.Node {
 }
 
 func (n PropertyFetch) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n PropertyFetch) Position() *node.Position {

node/expr/require.go

@@ -5,21 +5,19 @@ import (
 )
 
 type Require struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewRequire(Expression node.Node) node.Node {
 	return &Require{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n Require) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Require) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n Require) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/require_once.go

@@ -5,21 +5,19 @@ import (
 )
 
 type RequireOnce struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewRequireOnce(Expression node.Node) node.Node {
 	return &RequireOnce{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n RequireOnce) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n RequireOnce) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n RequireOnce) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/shell_exec.go

@@ -5,21 +5,19 @@ import (
 )
 
 type ShellExec struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Parts    []node.Node
 }
 
 func NewShellExec(Parts []node.Node) node.Node {
 	return &ShellExec{
-		map[string]interface{}{},
 		nil,
 		Parts,
 	}
 }
 
 func (n ShellExec) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ShellExec) Position() *node.Position {

node/expr/short_array.go

@@ -5,21 +5,19 @@ import (
 )
 
 type ShortArray struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Items    []node.Node
 }
 
 func NewShortArray(Items []node.Node) node.Node {
 	return &ShortArray{
-		map[string]interface{}{},
 		nil,
 		Items,
 	}
 }
 
 func (n ShortArray) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ShortArray) Position() *node.Position {

node/expr/short_list.go

@@ -5,21 +5,19 @@ import (
 )
 
 type ShortList struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Items    []node.Node
 }
 
 func NewShortList(Items []node.Node) node.Node {
 	return &ShortList{
-		map[string]interface{}{},
 		nil,
 		Items,
 	}
 }
 
 func (n ShortList) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n ShortList) Position() *node.Position {

node/expr/static_call.go

@@ -5,7 +5,6 @@ import (
 )
 
 type StaticCall struct {
-	attributes map[string]interface{}
 	position  *node.Position
 	Class     node.Node
 	Call      node.Node
@@ -14,7 +13,6 @@ type StaticCall struct {
 
 func NewStaticCall(Class node.Node, Call node.Node, Arguments []node.Node) node.Node {
 	return &StaticCall{
-		map[string]interface{}{},
 		nil,
 		Class,
 		Call,
@@ -23,7 +21,7 @@ func NewStaticCall(Class node.Node, Call node.Node, Arguments []node.Node) node.
 }
 
 func (n StaticCall) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n StaticCall) Position() *node.Position {

node/expr/static_property_fetch.go

@@ -5,7 +5,6 @@ import (
 )
 
 type StaticPropertyFetch struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Class    node.Node
 	Property node.Node
@@ -13,7 +12,6 @@ type StaticPropertyFetch struct {
 
 func NewStaticPropertyFetch(Class node.Node, Property node.Node) node.Node {
 	return &StaticPropertyFetch{
-		map[string]interface{}{},
 		nil,
 		Class,
 		Property,
@@ -21,7 +19,7 @@ func NewStaticPropertyFetch(Class node.Node, Property node.Node) node.Node {
 }
 
 func (n StaticPropertyFetch) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n StaticPropertyFetch) Position() *node.Position {

node/expr/ternary.go

@@ -5,7 +5,6 @@ import (
 )
 
 type Ternary struct {
-	attributes map[string]interface{}
 	position  *node.Position
 	Condition node.Node
 	IfTrue    node.Node
@@ -14,7 +13,6 @@ type Ternary struct {
 
 func NewTernary(Condition node.Node, IfTrue node.Node, IfFalse node.Node) node.Node {
 	return &Ternary{
-		map[string]interface{}{},
 		nil,
 		Condition,
 		IfTrue,
@@ -23,7 +21,7 @@ func NewTernary(Condition node.Node, IfTrue node.Node, IfFalse node.Node) node.N
 }
 
 func (n Ternary) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Ternary) Position() *node.Position {

node/expr/unary_minus.go

@@ -5,21 +5,19 @@ import (
 )
 
 type UnaryMinus struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewUnaryMinus(Expression node.Node) node.Node {
 	return &UnaryMinus{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n UnaryMinus) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n UnaryMinus) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n UnaryMinus) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/unary_plus.go

@@ -5,21 +5,19 @@ import (
 )
 
 type UnaryPlus struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewUnaryPlus(Expression node.Node) node.Node {
 	return &UnaryPlus{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n UnaryPlus) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n UnaryPlus) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n UnaryPlus) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/expr/variable.go

@@ -5,21 +5,19 @@ import (
 )
 
 type Variable struct {
-	attributes map[string]interface{}
 	position *node.Position
 	VarName  node.Node
 }
 
 func NewVariable(VarName node.Node) node.Node {
 	return &Variable{
-		map[string]interface{}{},
 		nil,
 		VarName,
 	}
 }
 
 func (n Variable) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Variable) Position() *node.Position {

node/expr/yield.go

@@ -5,7 +5,6 @@ import (
 )
 
 type Yield struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Key      node.Node
 	Value    node.Node
@@ -13,7 +12,6 @@ type Yield struct {
 
 func NewYield(Key node.Node, Value node.Node) node.Node {
 	return &Yield{
-		map[string]interface{}{},
 		nil,
 		Key,
 		Value,
@@ -21,7 +19,7 @@ func NewYield(Key node.Node, Value node.Node) node.Node {
 }
 
 func (n Yield) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Yield) Position() *node.Position {

node/expr/yield_from.go

@@ -5,21 +5,19 @@ import (
 )
 
 type YieldFrom struct {
-	attributes map[string]interface{}
 	position *node.Position
-	expr       node.Node
+	Expr     node.Node
 }
 
 func NewYieldFrom(Expression node.Node) node.Node {
 	return &YieldFrom{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n YieldFrom) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n YieldFrom) Position() *node.Position {
@@ -36,9 +34,9 @@ func (n YieldFrom) Walk(v node.Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/identifier.go

@@ -1,34 +1,21 @@
 package node
 
-import (
-	"github.com/z7zmey/php-parser/token"
-)
-
 type Identifier struct {
-	attributes map[string]interface{}
 	position *Position
+	Value    string
 }
 
-func NewIdentifier(token token.Token) Node {
+func NewIdentifier(Value string) Node {
 	return &Identifier{
-		map[string]interface{}{
-			"Value": token.Value,
-		},
 		nil,
+		Value,
 	}
 }
 
 func (n Identifier) Attributes() map[string]interface{} {
-	return n.attributes
-}
-
-func (n Identifier) Attribute(Key string) interface{} {
-	return n.attributes[Key]
-}
-
-func (n Identifier) SetAttribute(Key string, Value interface{}) Node {
-	n.attributes[Key] = Value
-	return n
+	return map[string]interface{}{
+		"Value": n.Value,
+	}
 }
 
 func (n Identifier) Position() *Position {

node/name/fully_qualified.go

@@ -11,13 +11,8 @@ type FullyQualified struct {
 func NewFullyQualified(Parts []node.Node) node.Node {
 	return &FullyQualified{
 		Name{
-			map[string]interface{}{},
 			nil,
 			Parts,
 		},
 	}
 }
-
-func (n FullyQualified) Attributes() map[string]interface{} {
-	return n.attributes
-}

node/name/name.go

@@ -5,21 +5,19 @@ import (
 )
 
 type Name struct {
-	attributes map[string]interface{}
 	position *node.Position
 	Parts    []node.Node
 }
 
 func NewName(Parts []node.Node) node.Node {
 	return &Name{
-		map[string]interface{}{},
 		nil,
 		Parts,
 	}
 }
 
 func (n Name) Attributes() map[string]interface{} {
-	return n.attributes
+	return nil
 }
 
 func (n Name) Position() *node.Position {

node/name/name_part.go

@@ -5,21 +5,21 @@ import (
 )
 
 type NamePart struct {
-	attributes map[string]interface{}
 	position *node.Position
+	Value    string
 }
 
 func NewNamePart(Value string) node.Node {
 	return &NamePart{
-		map[string]interface{}{
-			"Value": Value,
-		},
 		nil,
+		Value,
 	}
 }
 
 func (n NamePart) Attributes() map[string]interface{} {
-	return n.attributes
+	return map[string]interface{}{
+		"Value": n.Value,
+	}
 }
 
 func (n NamePart) Position() *node.Position {

node/name/relative.go

@@ -11,13 +11,8 @@ type Relative struct {
 func NewRelative(Parts []node.Node) node.Node {
 	return &Relative{
 		Name{
-			map[string]interface{}{},
 			nil,
 			Parts,
 		},
 	}
 }
-
-func (n Relative) Attributes() map[string]interface{} {
-	return n.attributes
-}

node/nullable.go

@@ -1,30 +1,19 @@
 package node
 
 type Nullable struct {
-	attributes map[string]interface{}
 	position *Position
-	expr       Node
+	Expr     Node
 }
 
 func NewNullable(Expression Node) Node {
 	return &Nullable{
-		map[string]interface{}{},
 		nil,
 		Expression,
 	}
 }
 
 func (n Nullable) Attributes() map[string]interface{} {
-	return n.attributes
-}
-
-func (n Nullable) Attribute(Key string) interface{} {
-	return n.attributes[Key]
-}
-
-func (n Nullable) SetAttribute(Key string, Value interface{}) Node {
-	n.attributes[Key] = Value
-	return n
+	return nil
 }
 
 func (n Nullable) Position() *Position {
@@ -41,9 +30,9 @@ func (n Nullable) Walk(v Visitor) {
 		return
 	}
 
-	if n.expr != nil {
-		vv := v.GetChildrenVisitor("expr")
-		n.expr.Walk(vv)
+	if n.Expr != nil {
+		vv := v.GetChildrenVisitor("Expr")
+		n.Expr.Walk(vv)
 	}
 
 	v.LeaveNode(n)

node/parameter.go

@@ -1,20 +1,19 @@
 package node
 
 type Parameter struct {
-	attributes   map[string]interface{}
 	position     *Position
+	ByRef        bool
+	Variadic     bool
 	VariableType Node
 	Variable     Node
 	DefaultValue Node
 }
 
-func NewParameter(VariableType Node, Variable Node, DefaultValue Node, byRef bool, variadic bool) Node {
+func NewParameter(VariableType Node, Variable Node, DefaultValue Node, ByRef bool, Variadic bool) Node {
 	return &Parameter{
-		map[string]interface{}{
-			"byRef":    byRef,
-			"variadic": variadic,
-		},
 		nil,
+		ByRef,
+		Variadic,
 		VariableType,
 		Variable,
 		DefaultValue,
@@ -22,16 +21,10 @@ func NewParameter(VariableType Node, Variable Node, DefaultValue Node, byRef boo
 }
 
 func (n Parameter) Attributes() map[string]interface{} {
-	return n.attributes
-}
-
-func (n Parameter) Attribute(Key string) interface{} {
-	return n.attributes[Key]
-}
-
-func (n Parameter) SetAttribute(Key string, Value interface{}) Node {
-	n.attributes[Key] = Value
-	return n
+	return map[string]interface{}{
+		"ByRef":    n.ByRef,
+		"Variadic": n.Variadic,
+	}
 }
 
 func (n Parameter) Position() *Position {