diff --git a/node/argument.go b/node/argument.go
index 94b4377..b33613f 100644
--- a/node/argument.go
+++ b/node/argument.go
@@ -9,7 +9,7 @@ type Argument struct {
 	Expr     Node
 }
 
-func NewArgument(Expression Node, Variadic bool) Node {
+func NewArgument(Expression Node, Variadic bool) *Argument {
 	return &Argument{
 		nil,
 		nil,
diff --git a/node/expr/array.go b/node/expr/array.go
index 197feac..4fb012a 100644
--- a/node/expr/array.go
+++ b/node/expr/array.go
@@ -11,7 +11,7 @@ type Array struct {
 	Items    []node.Node
 }
 
-func NewArray(Items []node.Node) node.Node {
+func NewArray(Items []node.Node) *Array {
 	return &Array{
 		nil,
 		nil,
diff --git a/node/expr/array_dim_fetch.go b/node/expr/array_dim_fetch.go
index ed51d52..56b9290 100644
--- a/node/expr/array_dim_fetch.go
+++ b/node/expr/array_dim_fetch.go
@@ -12,7 +12,7 @@ type ArrayDimFetch struct {
 	Dim      node.Node
 }
 
-func NewArrayDimFetch(Variable node.Node, Dim node.Node) node.Node {
+func NewArrayDimFetch(Variable node.Node, Dim node.Node) *ArrayDimFetch {
 	return &ArrayDimFetch{
 		nil,
 		nil,
diff --git a/node/expr/array_item.go b/node/expr/array_item.go
index e7533fc..68c7d8c 100644
--- a/node/expr/array_item.go
+++ b/node/expr/array_item.go
@@ -13,7 +13,7 @@ type ArrayItem struct {
 	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) *ArrayItem {
 	return &ArrayItem{
 		nil,
 		nil,
diff --git a/node/expr/assign_op/assign.go b/node/expr/assign_op/assign.go
index 9a0d476..22aa1a3 100644
--- a/node/expr/assign_op/assign.go
+++ b/node/expr/assign_op/assign.go
@@ -9,7 +9,7 @@ type Assign struct {
 	AssignOp
 }
 
-func NewAssign(Variable node.Node, Expression node.Node) node.Node {
+func NewAssign(Variable node.Node, Expression node.Node) *Assign {
 	return &Assign{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/assign_ref.go b/node/expr/assign_op/assign_ref.go
index 5ad5c5f..02a6491 100644
--- a/node/expr/assign_op/assign_ref.go
+++ b/node/expr/assign_op/assign_ref.go
@@ -9,7 +9,7 @@ type AssignRef struct {
 	AssignOp
 }
 
-func NewAssignRef(Variable node.Node, Expression node.Node) node.Node {
+func NewAssignRef(Variable node.Node, Expression node.Node) *AssignRef {
 	return &AssignRef{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/bitwise_and.go b/node/expr/assign_op/bitwise_and.go
index de63043..b72b51b 100644
--- a/node/expr/assign_op/bitwise_and.go
+++ b/node/expr/assign_op/bitwise_and.go
@@ -9,7 +9,7 @@ type BitwiseAnd struct {
 	AssignOp
 }
 
-func NewBitwiseAnd(Variable node.Node, Expression node.Node) node.Node {
+func NewBitwiseAnd(Variable node.Node, Expression node.Node) *BitwiseAnd {
 	return &BitwiseAnd{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/bitwise_or.go b/node/expr/assign_op/bitwise_or.go
index 3c1523b..25b8dab 100644
--- a/node/expr/assign_op/bitwise_or.go
+++ b/node/expr/assign_op/bitwise_or.go
@@ -9,7 +9,7 @@ type BitwiseOr struct {
 	AssignOp
 }
 
-func NewBitwiseOr(Variable node.Node, Expression node.Node) node.Node {
+func NewBitwiseOr(Variable node.Node, Expression node.Node) *BitwiseOr {
 	return &BitwiseOr{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/bitwise_xor.go b/node/expr/assign_op/bitwise_xor.go
index e378305..e0d1cc9 100644
--- a/node/expr/assign_op/bitwise_xor.go
+++ b/node/expr/assign_op/bitwise_xor.go
@@ -9,7 +9,7 @@ type BitwiseXor struct {
 	AssignOp
 }
 
-func NewBitwiseXor(Variable node.Node, Expression node.Node) node.Node {
+func NewBitwiseXor(Variable node.Node, Expression node.Node) *BitwiseXor {
 	return &BitwiseXor{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/concat.go b/node/expr/assign_op/concat.go
index f1e19e0..936a315 100644
--- a/node/expr/assign_op/concat.go
+++ b/node/expr/assign_op/concat.go
@@ -9,7 +9,7 @@ type Concat struct {
 	AssignOp
 }
 
-func NewConcat(Variable node.Node, Expression node.Node) node.Node {
+func NewConcat(Variable node.Node, Expression node.Node) *Concat {
 	return &Concat{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/div.go b/node/expr/assign_op/div.go
index fcc18c7..d93e277 100644
--- a/node/expr/assign_op/div.go
+++ b/node/expr/assign_op/div.go
@@ -9,7 +9,7 @@ type Div struct {
 	AssignOp
 }
 
-func NewDiv(Variable node.Node, Expression node.Node) node.Node {
+func NewDiv(Variable node.Node, Expression node.Node) *Div {
 	return &Div{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/minus.go b/node/expr/assign_op/minus.go
index de17c3a..72fdfab 100644
--- a/node/expr/assign_op/minus.go
+++ b/node/expr/assign_op/minus.go
@@ -9,7 +9,7 @@ type Minus struct {
 	AssignOp
 }
 
-func NewMinus(Variable node.Node, Expression node.Node) node.Node {
+func NewMinus(Variable node.Node, Expression node.Node) *Minus {
 	return &Minus{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/mod.go b/node/expr/assign_op/mod.go
index af24cf1..2f1c4af 100644
--- a/node/expr/assign_op/mod.go
+++ b/node/expr/assign_op/mod.go
@@ -9,7 +9,7 @@ type Mod struct {
 	AssignOp
 }
 
-func NewMod(Variable node.Node, Expression node.Node) node.Node {
+func NewMod(Variable node.Node, Expression node.Node) *Mod {
 	return &Mod{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/mul.go b/node/expr/assign_op/mul.go
index 4c5d205..8527f98 100644
--- a/node/expr/assign_op/mul.go
+++ b/node/expr/assign_op/mul.go
@@ -9,7 +9,7 @@ type Mul struct {
 	AssignOp
 }
 
-func NewMul(Variable node.Node, Expression node.Node) node.Node {
+func NewMul(Variable node.Node, Expression node.Node) *Mul {
 	return &Mul{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/plus.go b/node/expr/assign_op/plus.go
index 8d87d93..0e83294 100644
--- a/node/expr/assign_op/plus.go
+++ b/node/expr/assign_op/plus.go
@@ -9,7 +9,7 @@ type Plus struct {
 	AssignOp
 }
 
-func NewPlus(Variable node.Node, Expression node.Node) node.Node {
+func NewPlus(Variable node.Node, Expression node.Node) *Plus {
 	return &Plus{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/pow.go b/node/expr/assign_op/pow.go
index d984e82..d0c8800 100644
--- a/node/expr/assign_op/pow.go
+++ b/node/expr/assign_op/pow.go
@@ -9,7 +9,7 @@ type Pow struct {
 	AssignOp
 }
 
-func NewPow(Variable node.Node, Expression node.Node) node.Node {
+func NewPow(Variable node.Node, Expression node.Node) *Pow {
 	return &Pow{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/shift_left.go b/node/expr/assign_op/shift_left.go
index 52be668..4a121ef 100644
--- a/node/expr/assign_op/shift_left.go
+++ b/node/expr/assign_op/shift_left.go
@@ -9,7 +9,7 @@ type ShiftLeft struct {
 	AssignOp
 }
 
-func NewShiftLeft(Variable node.Node, Expression node.Node) node.Node {
+func NewShiftLeft(Variable node.Node, Expression node.Node) *ShiftLeft {
 	return &ShiftLeft{
 		AssignOp{
 			nil,
diff --git a/node/expr/assign_op/shift_right.go b/node/expr/assign_op/shift_right.go
index 8b1a08e..05d23a9 100644
--- a/node/expr/assign_op/shift_right.go
+++ b/node/expr/assign_op/shift_right.go
@@ -9,7 +9,7 @@ type ShiftRight struct {
 	AssignOp
 }
 
-func NewShiftRight(Variable node.Node, Expression node.Node) node.Node {
+func NewShiftRight(Variable node.Node, Expression node.Node) *ShiftRight {
 	return &ShiftRight{
 		AssignOp{
 			nil,
diff --git a/node/expr/binary_op/bitwise_and.go b/node/expr/binary_op/bitwise_and.go
index a7e887e..31299eb 100644
--- a/node/expr/binary_op/bitwise_and.go
+++ b/node/expr/binary_op/bitwise_and.go
@@ -9,7 +9,7 @@ type BitwiseAnd struct {
 	BinaryOp
 }
 
-func NewBitwiseAnd(Variable node.Node, Expression node.Node) node.Node {
+func NewBitwiseAnd(Variable node.Node, Expression node.Node) *BitwiseAnd {
 	return &BitwiseAnd{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/bitwise_or.go b/node/expr/binary_op/bitwise_or.go
index f56134b..0f961a9 100644
--- a/node/expr/binary_op/bitwise_or.go
+++ b/node/expr/binary_op/bitwise_or.go
@@ -9,7 +9,7 @@ type BitwiseOr struct {
 	BinaryOp
 }
 
-func NewBitwiseOr(Variable node.Node, Expression node.Node) node.Node {
+func NewBitwiseOr(Variable node.Node, Expression node.Node) *BitwiseOr {
 	return &BitwiseOr{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/bitwise_xor.go b/node/expr/binary_op/bitwise_xor.go
index 73c2957..0dcc01c 100644
--- a/node/expr/binary_op/bitwise_xor.go
+++ b/node/expr/binary_op/bitwise_xor.go
@@ -9,7 +9,7 @@ type BitwiseXor struct {
 	BinaryOp
 }
 
-func NewBitwiseXor(Variable node.Node, Expression node.Node) node.Node {
+func NewBitwiseXor(Variable node.Node, Expression node.Node) *BitwiseXor {
 	return &BitwiseXor{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/boolean_and.go b/node/expr/binary_op/boolean_and.go
index ec3a809..2de26ba 100644
--- a/node/expr/binary_op/boolean_and.go
+++ b/node/expr/binary_op/boolean_and.go
@@ -9,7 +9,7 @@ type BooleanAnd struct {
 	BinaryOp
 }
 
-func NewBooleanAnd(Variable node.Node, Expression node.Node) node.Node {
+func NewBooleanAnd(Variable node.Node, Expression node.Node) *BooleanAnd {
 	return &BooleanAnd{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/boolean_or.go b/node/expr/binary_op/boolean_or.go
index 8fa9d96..9e50d23 100644
--- a/node/expr/binary_op/boolean_or.go
+++ b/node/expr/binary_op/boolean_or.go
@@ -9,7 +9,7 @@ type BooleanOr struct {
 	BinaryOp
 }
 
-func NewBooleanOr(Variable node.Node, Expression node.Node) node.Node {
+func NewBooleanOr(Variable node.Node, Expression node.Node) *BooleanOr {
 	return &BooleanOr{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/coalesce.go b/node/expr/binary_op/coalesce.go
index df4d0ed..a0e3b21 100644
--- a/node/expr/binary_op/coalesce.go
+++ b/node/expr/binary_op/coalesce.go
@@ -9,7 +9,7 @@ type Coalesce struct {
 	BinaryOp
 }
 
-func NewCoalesce(Variable node.Node, Expression node.Node) node.Node {
+func NewCoalesce(Variable node.Node, Expression node.Node) *Coalesce {
 	return &Coalesce{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/concat.go b/node/expr/binary_op/concat.go
index 422f49c..03c4e56 100644
--- a/node/expr/binary_op/concat.go
+++ b/node/expr/binary_op/concat.go
@@ -9,7 +9,7 @@ type Concat struct {
 	BinaryOp
 }
 
-func NewConcat(Variable node.Node, Expression node.Node) node.Node {
+func NewConcat(Variable node.Node, Expression node.Node) *Concat {
 	return &Concat{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/div.go b/node/expr/binary_op/div.go
index a7da01f..da07024 100644
--- a/node/expr/binary_op/div.go
+++ b/node/expr/binary_op/div.go
@@ -9,7 +9,7 @@ type Div struct {
 	BinaryOp
 }
 
-func NewDiv(Variable node.Node, Expression node.Node) node.Node {
+func NewDiv(Variable node.Node, Expression node.Node) *Div {
 	return &Div{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/equal.go b/node/expr/binary_op/equal.go
index cdd7983..223987e 100644
--- a/node/expr/binary_op/equal.go
+++ b/node/expr/binary_op/equal.go
@@ -9,7 +9,7 @@ type Equal struct {
 	BinaryOp
 }
 
-func NewEqual(Variable node.Node, Expression node.Node) node.Node {
+func NewEqual(Variable node.Node, Expression node.Node) *Equal {
 	return &Equal{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/greater.go b/node/expr/binary_op/greater.go
index 2544192..733eff7 100644
--- a/node/expr/binary_op/greater.go
+++ b/node/expr/binary_op/greater.go
@@ -9,7 +9,7 @@ type Greater struct {
 	BinaryOp
 }
 
-func NewGreater(Variable node.Node, Expression node.Node) node.Node {
+func NewGreater(Variable node.Node, Expression node.Node) *Greater {
 	return &Greater{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/greater_or_equal.go b/node/expr/binary_op/greater_or_equal.go
index 04b8834..6a6f1d7 100644
--- a/node/expr/binary_op/greater_or_equal.go
+++ b/node/expr/binary_op/greater_or_equal.go
@@ -9,7 +9,7 @@ type GreaterOrEqual struct {
 	BinaryOp
 }
 
-func NewGreaterOrEqual(Variable node.Node, Expression node.Node) node.Node {
+func NewGreaterOrEqual(Variable node.Node, Expression node.Node) *GreaterOrEqual {
 	return &GreaterOrEqual{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/identical.go b/node/expr/binary_op/identical.go
index 9f77a1e..9769518 100644
--- a/node/expr/binary_op/identical.go
+++ b/node/expr/binary_op/identical.go
@@ -9,7 +9,7 @@ type Identical struct {
 	BinaryOp
 }
 
-func NewIdentical(Variable node.Node, Expression node.Node) node.Node {
+func NewIdentical(Variable node.Node, Expression node.Node) *Identical {
 	return &Identical{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/logical_and.go b/node/expr/binary_op/logical_and.go
index 4ffb950..de4af67 100644
--- a/node/expr/binary_op/logical_and.go
+++ b/node/expr/binary_op/logical_and.go
@@ -9,7 +9,7 @@ type LogicalAnd struct {
 	BinaryOp
 }
 
-func NewLogicalAnd(Variable node.Node, Expression node.Node) node.Node {
+func NewLogicalAnd(Variable node.Node, Expression node.Node) *LogicalAnd {
 	return &LogicalAnd{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/logical_or.go b/node/expr/binary_op/logical_or.go
index 8407b5d..2e9311d 100644
--- a/node/expr/binary_op/logical_or.go
+++ b/node/expr/binary_op/logical_or.go
@@ -9,7 +9,7 @@ type LogicalOr struct {
 	BinaryOp
 }
 
-func NewLogicalOr(Variable node.Node, Expression node.Node) node.Node {
+func NewLogicalOr(Variable node.Node, Expression node.Node) *LogicalOr {
 	return &LogicalOr{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/logical_xor.go b/node/expr/binary_op/logical_xor.go
index 72c6034..0bcbaa6 100644
--- a/node/expr/binary_op/logical_xor.go
+++ b/node/expr/binary_op/logical_xor.go
@@ -9,7 +9,7 @@ type LogicalXor struct {
 	BinaryOp
 }
 
-func NewLogicalXor(Variable node.Node, Expression node.Node) node.Node {
+func NewLogicalXor(Variable node.Node, Expression node.Node) *LogicalXor {
 	return &LogicalXor{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/minus.go b/node/expr/binary_op/minus.go
index e6d6694..8ea6241 100644
--- a/node/expr/binary_op/minus.go
+++ b/node/expr/binary_op/minus.go
@@ -9,7 +9,7 @@ type Minus struct {
 	BinaryOp
 }
 
-func NewMinus(Variable node.Node, Expression node.Node) node.Node {
+func NewMinus(Variable node.Node, Expression node.Node) *Minus {
 	return &Minus{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/mod.go b/node/expr/binary_op/mod.go
index 48ea0b5..9e591b1 100644
--- a/node/expr/binary_op/mod.go
+++ b/node/expr/binary_op/mod.go
@@ -9,7 +9,7 @@ type Mod struct {
 	BinaryOp
 }
 
-func NewMod(Variable node.Node, Expression node.Node) node.Node {
+func NewMod(Variable node.Node, Expression node.Node) *Mod {
 	return &Mod{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/mul.go b/node/expr/binary_op/mul.go
index f47ec0a..0760067 100644
--- a/node/expr/binary_op/mul.go
+++ b/node/expr/binary_op/mul.go
@@ -9,7 +9,7 @@ type Mul struct {
 	BinaryOp
 }
 
-func NewMul(Variable node.Node, Expression node.Node) node.Node {
+func NewMul(Variable node.Node, Expression node.Node) *Mul {
 	return &Mul{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/not_equal.go b/node/expr/binary_op/not_equal.go
index 979f3d8..0dfd2d3 100644
--- a/node/expr/binary_op/not_equal.go
+++ b/node/expr/binary_op/not_equal.go
@@ -9,7 +9,7 @@ type NotEqual struct {
 	BinaryOp
 }
 
-func NewNotEqual(Variable node.Node, Expression node.Node) node.Node {
+func NewNotEqual(Variable node.Node, Expression node.Node) *NotEqual {
 	return &NotEqual{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/not_identical.go b/node/expr/binary_op/not_identical.go
index 6fc1a50..2881872 100644
--- a/node/expr/binary_op/not_identical.go
+++ b/node/expr/binary_op/not_identical.go
@@ -9,7 +9,7 @@ type NotIdentical struct {
 	BinaryOp
 }
 
-func NewNotIdentical(Variable node.Node, Expression node.Node) node.Node {
+func NewNotIdentical(Variable node.Node, Expression node.Node) *NotIdentical {
 	return &NotIdentical{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/plus.go b/node/expr/binary_op/plus.go
index c20b206..bcc5acc 100644
--- a/node/expr/binary_op/plus.go
+++ b/node/expr/binary_op/plus.go
@@ -9,7 +9,7 @@ type Plus struct {
 	BinaryOp
 }
 
-func NewPlus(Variable node.Node, Expression node.Node) node.Node {
+func NewPlus(Variable node.Node, Expression node.Node) *Plus {
 	return &Plus{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/pow.go b/node/expr/binary_op/pow.go
index 0d85662..5d7f485 100644
--- a/node/expr/binary_op/pow.go
+++ b/node/expr/binary_op/pow.go
@@ -9,7 +9,7 @@ type Pow struct {
 	BinaryOp
 }
 
-func NewPow(Variable node.Node, Expression node.Node) node.Node {
+func NewPow(Variable node.Node, Expression node.Node) *Pow {
 	return &Pow{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/shift_left.go b/node/expr/binary_op/shift_left.go
index 2772926..5fd2205 100644
--- a/node/expr/binary_op/shift_left.go
+++ b/node/expr/binary_op/shift_left.go
@@ -9,7 +9,7 @@ type ShiftLeft struct {
 	BinaryOp
 }
 
-func NewShiftLeft(Variable node.Node, Expression node.Node) node.Node {
+func NewShiftLeft(Variable node.Node, Expression node.Node) *ShiftLeft {
 	return &ShiftLeft{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/shift_right.go b/node/expr/binary_op/shift_right.go
index 1e5acb5..37febc9 100644
--- a/node/expr/binary_op/shift_right.go
+++ b/node/expr/binary_op/shift_right.go
@@ -9,7 +9,7 @@ type ShiftRight struct {
 	BinaryOp
 }
 
-func NewShiftRight(Variable node.Node, Expression node.Node) node.Node {
+func NewShiftRight(Variable node.Node, Expression node.Node) *ShiftRight {
 	return &ShiftRight{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/smaller.go b/node/expr/binary_op/smaller.go
index 7438575..44aa053 100644
--- a/node/expr/binary_op/smaller.go
+++ b/node/expr/binary_op/smaller.go
@@ -9,7 +9,7 @@ type Smaller struct {
 	BinaryOp
 }
 
-func NewSmaller(Variable node.Node, Expression node.Node) node.Node {
+func NewSmaller(Variable node.Node, Expression node.Node) *Smaller {
 	return &Smaller{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/smaller_or_equal.go b/node/expr/binary_op/smaller_or_equal.go
index 5d874a8..a9f0274 100644
--- a/node/expr/binary_op/smaller_or_equal.go
+++ b/node/expr/binary_op/smaller_or_equal.go
@@ -9,7 +9,7 @@ type SmallerOrEqual struct {
 	BinaryOp
 }
 
-func NewSmallerOrEqual(Variable node.Node, Expression node.Node) node.Node {
+func NewSmallerOrEqual(Variable node.Node, Expression node.Node) *SmallerOrEqual {
 	return &SmallerOrEqual{
 		BinaryOp{
 			nil,
diff --git a/node/expr/binary_op/spaceship.go b/node/expr/binary_op/spaceship.go
index 888d147..8d5120f 100644
--- a/node/expr/binary_op/spaceship.go
+++ b/node/expr/binary_op/spaceship.go
@@ -9,7 +9,7 @@ type Spaceship struct {
 	BinaryOp
 }
 
-func NewSpaceship(Variable node.Node, Expression node.Node) node.Node {
+func NewSpaceship(Variable node.Node, Expression node.Node) *Spaceship {
 	return &Spaceship{
 		BinaryOp{
 			nil,
diff --git a/node/expr/bitwise_not.go b/node/expr/bitwise_not.go
index 205fd1a..65b1673 100644
--- a/node/expr/bitwise_not.go
+++ b/node/expr/bitwise_not.go
@@ -11,7 +11,7 @@ type BitwiseNot struct {
 	Expr     node.Node
 }
 
-func NewBitwiseNot(Expression node.Node) node.Node {
+func NewBitwiseNot(Expression node.Node) *BitwiseNot {
 	return &BitwiseNot{
 		nil,
 		nil,
diff --git a/node/expr/boolean_not.go b/node/expr/boolean_not.go
index b7beb7e..4a7576d 100644
--- a/node/expr/boolean_not.go
+++ b/node/expr/boolean_not.go
@@ -11,7 +11,7 @@ type BooleanNot struct {
 	Expr     node.Node
 }
 
-func NewBooleanNot(Expression node.Node) node.Node {
+func NewBooleanNot(Expression node.Node) *BooleanNot {
 	return &BooleanNot{
 		nil,
 		nil,
diff --git a/node/expr/cast/cast_array.go b/node/expr/cast/cast_array.go
index 2403a1a..4741946 100644
--- a/node/expr/cast/cast_array.go
+++ b/node/expr/cast/cast_array.go
@@ -9,7 +9,7 @@ type CastArray struct {
 	Cast
 }
 
-func NewCastArray(Expr node.Node) node.Node {
+func NewCastArray(Expr node.Node) *CastArray {
 	return &CastArray{
 		Cast{
 			nil,
diff --git a/node/expr/cast/cast_bool.go b/node/expr/cast/cast_bool.go
index 583b839..eaed8c4 100644
--- a/node/expr/cast/cast_bool.go
+++ b/node/expr/cast/cast_bool.go
@@ -9,7 +9,7 @@ type CastBool struct {
 	Cast
 }
 
-func NewCastBool(Expr node.Node) node.Node {
+func NewCastBool(Expr node.Node) *CastBool {
 	return &CastBool{
 		Cast{
 			nil,
diff --git a/node/expr/cast/cast_double.go b/node/expr/cast/cast_double.go
index da06a18..34b19a0 100644
--- a/node/expr/cast/cast_double.go
+++ b/node/expr/cast/cast_double.go
@@ -9,7 +9,7 @@ type CastDouble struct {
 	Cast
 }
 
-func NewCastDouble(Expr node.Node) node.Node {
+func NewCastDouble(Expr node.Node) *CastDouble {
 	return &CastDouble{
 		Cast{
 			nil,
diff --git a/node/expr/cast/cast_int.go b/node/expr/cast/cast_int.go
index 44e57c1..d7aada8 100644
--- a/node/expr/cast/cast_int.go
+++ b/node/expr/cast/cast_int.go
@@ -9,7 +9,7 @@ type CastInt struct {
 	Cast
 }
 
-func NewCastInt(Expr node.Node) node.Node {
+func NewCastInt(Expr node.Node) *CastInt {
 	return &CastInt{
 		Cast{
 			nil,
diff --git a/node/expr/cast/cast_object.go b/node/expr/cast/cast_object.go
index 8c4079b..9e03373 100644
--- a/node/expr/cast/cast_object.go
+++ b/node/expr/cast/cast_object.go
@@ -9,7 +9,7 @@ type CastObject struct {
 	Cast
 }
 
-func NewCastObject(Expr node.Node) node.Node {
+func NewCastObject(Expr node.Node) *CastObject {
 	return &CastObject{
 		Cast{
 			nil,
diff --git a/node/expr/cast/cast_string.go b/node/expr/cast/cast_string.go
index 1057678..5ae3b53 100644
--- a/node/expr/cast/cast_string.go
+++ b/node/expr/cast/cast_string.go
@@ -9,7 +9,7 @@ type CastString struct {
 	Cast
 }
 
-func NewCastString(Expr node.Node) node.Node {
+func NewCastString(Expr node.Node) *CastString {
 	return &CastString{
 		Cast{
 			nil,
diff --git a/node/expr/cast/cast_unset.go b/node/expr/cast/cast_unset.go
index b97c867..4c15130 100644
--- a/node/expr/cast/cast_unset.go
+++ b/node/expr/cast/cast_unset.go
@@ -9,7 +9,7 @@ type CastUnset struct {
 	Cast
 }
 
-func NewCastUnset(Expr node.Node) node.Node {
+func NewCastUnset(Expr node.Node) *CastUnset {
 	return &CastUnset{
 		Cast{
 			nil,
diff --git a/node/expr/class_const_fetch.go b/node/expr/class_const_fetch.go
index a0e0fa4..4826fc5 100644
--- a/node/expr/class_const_fetch.go
+++ b/node/expr/class_const_fetch.go
@@ -12,7 +12,7 @@ type ClassConstFetch struct {
 	ConstantName node.Node
 }
 
-func NewClassConstFetch(Class node.Node, ConstantName node.Node) node.Node {
+func NewClassConstFetch(Class node.Node, ConstantName node.Node) *ClassConstFetch {
 	return &ClassConstFetch{
 		nil,
 		nil,
diff --git a/node/expr/clone.go b/node/expr/clone.go
index 40baff3..8d81f9a 100644
--- a/node/expr/clone.go
+++ b/node/expr/clone.go
@@ -11,7 +11,7 @@ type Clone struct {
 	Expr     node.Node
 }
 
-func NewClone(Expression node.Node) node.Node {
+func NewClone(Expression node.Node) *Clone {
 	return &Clone{
 		nil,
 		nil,
diff --git a/node/expr/closure.go b/node/expr/closure.go
index d1a665f..1f6ff94 100644
--- a/node/expr/closure.go
+++ b/node/expr/closure.go
@@ -17,7 +17,7 @@ type Closure struct {
 	Stmts         []node.Node
 }
 
-func NewClosure(Params []node.Node, Uses []node.Node, ReturnType node.Node, Stmts []node.Node, Static bool, ReturnsRef 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) *Closure {
 	return &Closure{
 		nil,
 		nil,
diff --git a/node/expr/closure_use.go b/node/expr/closure_use.go
index eb7662a..33124cb 100644
--- a/node/expr/closure_use.go
+++ b/node/expr/closure_use.go
@@ -12,7 +12,7 @@ type ClusureUse struct {
 	Variable node.Node
 }
 
-func NewClusureUse(Variable node.Node, ByRef bool) node.Node {
+func NewClusureUse(Variable node.Node, ByRef bool) *ClusureUse {
 	return &ClusureUse{
 		nil,
 		nil,
diff --git a/node/expr/const_fetch.go b/node/expr/const_fetch.go
index 50347f8..46842e0 100644
--- a/node/expr/const_fetch.go
+++ b/node/expr/const_fetch.go
@@ -11,7 +11,7 @@ type ConstFetch struct {
 	Constant node.Node
 }
 
-func NewConstFetch(Constant node.Node) node.Node {
+func NewConstFetch(Constant node.Node) *ConstFetch {
 	return &ConstFetch{
 		nil,
 		nil,
diff --git a/node/expr/empty.go b/node/expr/empty.go
index a323e06..e83d2e3 100644
--- a/node/expr/empty.go
+++ b/node/expr/empty.go
@@ -11,7 +11,7 @@ type Empty struct {
 	Expr     node.Node
 }
 
-func NewEmpty(Expression node.Node) node.Node {
+func NewEmpty(Expression node.Node) *Empty {
 	return &Empty{
 		nil,
 		nil,
diff --git a/node/expr/error_suppress.go b/node/expr/error_suppress.go
index aea40b9..a5c601b 100644
--- a/node/expr/error_suppress.go
+++ b/node/expr/error_suppress.go
@@ -11,7 +11,7 @@ type ErrorSuppress struct {
 	Expr     node.Node
 }
 
-func NewErrorSuppress(Expression node.Node) node.Node {
+func NewErrorSuppress(Expression node.Node) *ErrorSuppress {
 	return &ErrorSuppress{
 		nil,
 		nil,
diff --git a/node/expr/eval.go b/node/expr/eval.go
index 664ea32..69c6c47 100644
--- a/node/expr/eval.go
+++ b/node/expr/eval.go
@@ -11,7 +11,7 @@ type Eval struct {
 	Expr     node.Node
 }
 
-func NewEval(Expression node.Node) node.Node {
+func NewEval(Expression node.Node) *Eval {
 	return &Eval{
 		nil,
 		nil,
diff --git a/node/expr/exit.go b/node/expr/exit.go
index 3770d97..ea487e9 100644
--- a/node/expr/exit.go
+++ b/node/expr/exit.go
@@ -12,7 +12,7 @@ type Exit struct {
 	IsDie    bool
 }
 
-func NewExit(Expr node.Node, IsDie bool) node.Node {
+func NewExit(Expr node.Node, IsDie bool) *Exit {
 	return &Exit{
 		nil,
 		nil,
diff --git a/node/expr/function_call.go b/node/expr/function_call.go
index e36f879..5f7e824 100644
--- a/node/expr/function_call.go
+++ b/node/expr/function_call.go
@@ -12,7 +12,7 @@ type FunctionCall struct {
 	Arguments []node.Node
 }
 
-func NewFunctionCall(Function node.Node, Arguments []node.Node) node.Node {
+func NewFunctionCall(Function node.Node, Arguments []node.Node) *FunctionCall {
 	return &FunctionCall{
 		nil,
 		nil,
diff --git a/node/expr/include.go b/node/expr/include.go
index 3860a99..adfcdf5 100644
--- a/node/expr/include.go
+++ b/node/expr/include.go
@@ -11,7 +11,7 @@ type Include struct {
 	Expr     node.Node
 }
 
-func NewInclude(Expression node.Node) node.Node {
+func NewInclude(Expression node.Node) *Include {
 	return &Include{
 		nil,
 		nil,
diff --git a/node/expr/include_once.go b/node/expr/include_once.go
index c9accd7..a384d01 100644
--- a/node/expr/include_once.go
+++ b/node/expr/include_once.go
@@ -11,7 +11,7 @@ type IncludeOnce struct {
 	Expr     node.Node
 }
 
-func NewIncludeOnce(Expression node.Node) node.Node {
+func NewIncludeOnce(Expression node.Node) *IncludeOnce {
 	return &IncludeOnce{
 		nil,
 		nil,
diff --git a/node/expr/instance_of.go b/node/expr/instance_of.go
index b9ecd86..f135cbc 100644
--- a/node/expr/instance_of.go
+++ b/node/expr/instance_of.go
@@ -12,7 +12,7 @@ type InstanceOf struct {
 	Class    node.Node
 }
 
-func NewInstanceOf(Expr node.Node, Class node.Node) node.Node {
+func NewInstanceOf(Expr node.Node, Class node.Node) *InstanceOf {
 	return &InstanceOf{
 		nil,
 		nil,
diff --git a/node/expr/isset.go b/node/expr/isset.go
index 125372b..81d5b75 100644
--- a/node/expr/isset.go
+++ b/node/expr/isset.go
@@ -11,7 +11,7 @@ type Isset struct {
 	Variables []node.Node
 }
 
-func NewIsset(Variables []node.Node) node.Node {
+func NewIsset(Variables []node.Node) *Isset {
 	return &Isset{
 		nil,
 		nil,
diff --git a/node/expr/list.go b/node/expr/list.go
index 860a6a4..28a439f 100644
--- a/node/expr/list.go
+++ b/node/expr/list.go
@@ -11,7 +11,7 @@ type List struct {
 	Items    []node.Node
 }
 
-func NewList(Items []node.Node) node.Node {
+func NewList(Items []node.Node) *List {
 	return &List{
 		nil,
 		nil,
diff --git a/node/expr/method_call.go b/node/expr/method_call.go
index a5669b5..cfb6a8d 100644
--- a/node/expr/method_call.go
+++ b/node/expr/method_call.go
@@ -13,7 +13,7 @@ type MethodCall struct {
 	Arguments []node.Node
 }
 
-func NewMethodCall(Variable node.Node, Method node.Node, Arguments []node.Node) node.Node {
+func NewMethodCall(Variable node.Node, Method node.Node, Arguments []node.Node) *MethodCall {
 	return &MethodCall{
 		nil,
 		nil,
diff --git a/node/expr/new.go b/node/expr/new.go
index 5404043..c318d47 100644
--- a/node/expr/new.go
+++ b/node/expr/new.go
@@ -12,7 +12,7 @@ type New struct {
 	Arguments []node.Node
 }
 
-func NewNew(Class node.Node, Arguments []node.Node) node.Node {
+func NewNew(Class node.Node, Arguments []node.Node) *New {
 	return &New{
 		nil,
 		nil,
diff --git a/node/expr/post_dec.go b/node/expr/post_dec.go
index a231c67..ee12def 100644
--- a/node/expr/post_dec.go
+++ b/node/expr/post_dec.go
@@ -11,7 +11,7 @@ type PostDec struct {
 	Variable node.Node
 }
 
-func NewPostDec(Variable node.Node) node.Node {
+func NewPostDec(Variable node.Node) *PostDec {
 	return &PostDec{
 		nil,
 		nil,
diff --git a/node/expr/post_inc.go b/node/expr/post_inc.go
index 6503bfc..cd48647 100644
--- a/node/expr/post_inc.go
+++ b/node/expr/post_inc.go
@@ -11,7 +11,7 @@ type PostInc struct {
 	Variable node.Node
 }
 
-func NewPostInc(Variable node.Node) node.Node {
+func NewPostInc(Variable node.Node) *PostInc {
 	return &PostInc{
 		nil,
 		nil,
diff --git a/node/expr/pre_dec.go b/node/expr/pre_dec.go
index 8991bc1..4d044e8 100644
--- a/node/expr/pre_dec.go
+++ b/node/expr/pre_dec.go
@@ -11,7 +11,7 @@ type PreDec struct {
 	Variable node.Node
 }
 
-func NewPreDec(Variable node.Node) node.Node {
+func NewPreDec(Variable node.Node) *PreDec {
 	return &PreDec{
 		nil,
 		nil,
diff --git a/node/expr/pre_inc.go b/node/expr/pre_inc.go
index 2b117a5..505725e 100644
--- a/node/expr/pre_inc.go
+++ b/node/expr/pre_inc.go
@@ -11,7 +11,7 @@ type PreInc struct {
 	Variable node.Node
 }
 
-func NewPreInc(Variable node.Node) node.Node {
+func NewPreInc(Variable node.Node) *PreInc {
 	return &PreInc{
 		nil,
 		nil,
diff --git a/node/expr/print.go b/node/expr/print.go
index 0867b9b..91b6542 100644
--- a/node/expr/print.go
+++ b/node/expr/print.go
@@ -11,7 +11,7 @@ type Print struct {
 	Expr     node.Node
 }
 
-func NewPrint(Expression node.Node) node.Node {
+func NewPrint(Expression node.Node) *Print {
 	return &Print{
 		nil,
 		nil,
diff --git a/node/expr/property_fetch.go b/node/expr/property_fetch.go
index e5701d3..7705558 100644
--- a/node/expr/property_fetch.go
+++ b/node/expr/property_fetch.go
@@ -12,7 +12,7 @@ type PropertyFetch struct {
 	Property node.Node
 }
 
-func NewPropertyFetch(Variable node.Node, Property node.Node) node.Node {
+func NewPropertyFetch(Variable node.Node, Property node.Node) *PropertyFetch {
 	return &PropertyFetch{
 		nil,
 		nil,
diff --git a/node/expr/require.go b/node/expr/require.go
index 66a7bc9..8b662b6 100644
--- a/node/expr/require.go
+++ b/node/expr/require.go
@@ -11,7 +11,7 @@ type Require struct {
 	Expr     node.Node
 }
 
-func NewRequire(Expression node.Node) node.Node {
+func NewRequire(Expression node.Node) *Require {
 	return &Require{
 		nil,
 		nil,
diff --git a/node/expr/require_once.go b/node/expr/require_once.go
index e4886c8..f5dfb9e 100644
--- a/node/expr/require_once.go
+++ b/node/expr/require_once.go
@@ -11,7 +11,7 @@ type RequireOnce struct {
 	Expr     node.Node
 }
 
-func NewRequireOnce(Expression node.Node) node.Node {
+func NewRequireOnce(Expression node.Node) *RequireOnce {
 	return &RequireOnce{
 		nil,
 		nil,
diff --git a/node/expr/shell_exec.go b/node/expr/shell_exec.go
index 25fd0ae..bf6df24 100644
--- a/node/expr/shell_exec.go
+++ b/node/expr/shell_exec.go
@@ -11,7 +11,7 @@ type ShellExec struct {
 	Parts    []node.Node
 }
 
-func NewShellExec(Parts []node.Node) node.Node {
+func NewShellExec(Parts []node.Node) *ShellExec {
 	return &ShellExec{
 		nil,
 		nil,
diff --git a/node/expr/short_array.go b/node/expr/short_array.go
index e959a87..43574d0 100644
--- a/node/expr/short_array.go
+++ b/node/expr/short_array.go
@@ -11,7 +11,7 @@ type ShortArray struct {
 	Items    []node.Node
 }
 
-func NewShortArray(Items []node.Node) node.Node {
+func NewShortArray(Items []node.Node) *ShortArray {
 	return &ShortArray{
 		nil,
 		nil,
diff --git a/node/expr/short_list.go b/node/expr/short_list.go
index b5c53b5..95484bf 100644
--- a/node/expr/short_list.go
+++ b/node/expr/short_list.go
@@ -11,7 +11,7 @@ type ShortList struct {
 	Items    []node.Node
 }
 
-func NewShortList(Items []node.Node) node.Node {
+func NewShortList(Items []node.Node) *ShortList {
 	return &ShortList{
 		nil,
 		nil,
diff --git a/node/expr/static_call.go b/node/expr/static_call.go
index 009c7a5..13ea6a9 100644
--- a/node/expr/static_call.go
+++ b/node/expr/static_call.go
@@ -13,7 +13,7 @@ type StaticCall struct {
 	Arguments []node.Node
 }
 
-func NewStaticCall(Class node.Node, Call node.Node, Arguments []node.Node) node.Node {
+func NewStaticCall(Class node.Node, Call node.Node, Arguments []node.Node) *StaticCall {
 	return &StaticCall{
 		nil,
 		nil,
diff --git a/node/expr/static_property_fetch.go b/node/expr/static_property_fetch.go
index 0bce323..5f460a1 100644
--- a/node/expr/static_property_fetch.go
+++ b/node/expr/static_property_fetch.go
@@ -12,7 +12,7 @@ type StaticPropertyFetch struct {
 	Property node.Node
 }
 
-func NewStaticPropertyFetch(Class node.Node, Property node.Node) node.Node {
+func NewStaticPropertyFetch(Class node.Node, Property node.Node) *StaticPropertyFetch {
 	return &StaticPropertyFetch{
 		nil,
 		nil,
diff --git a/node/expr/ternary.go b/node/expr/ternary.go
index 739f375..8c6b96e 100644
--- a/node/expr/ternary.go
+++ b/node/expr/ternary.go
@@ -13,7 +13,7 @@ type Ternary struct {
 	IfFalse   node.Node
 }
 
-func NewTernary(Condition node.Node, IfTrue node.Node, IfFalse node.Node) node.Node {
+func NewTernary(Condition node.Node, IfTrue node.Node, IfFalse node.Node) *Ternary {
 	return &Ternary{
 		nil,
 		nil,
diff --git a/node/expr/unary_minus.go b/node/expr/unary_minus.go
index c3e8c87..085a83f 100644
--- a/node/expr/unary_minus.go
+++ b/node/expr/unary_minus.go
@@ -11,7 +11,7 @@ type UnaryMinus struct {
 	Expr     node.Node
 }
 
-func NewUnaryMinus(Expression node.Node) node.Node {
+func NewUnaryMinus(Expression node.Node) *UnaryMinus {
 	return &UnaryMinus{
 		nil,
 		nil,
diff --git a/node/expr/unary_plus.go b/node/expr/unary_plus.go
index 921b48e..55727f2 100644
--- a/node/expr/unary_plus.go
+++ b/node/expr/unary_plus.go
@@ -11,7 +11,7 @@ type UnaryPlus struct {
 	Expr     node.Node
 }
 
-func NewUnaryPlus(Expression node.Node) node.Node {
+func NewUnaryPlus(Expression node.Node) *UnaryPlus {
 	return &UnaryPlus{
 		nil,
 		nil,
diff --git a/node/expr/variable.go b/node/expr/variable.go
index b54799b..6301e09 100644
--- a/node/expr/variable.go
+++ b/node/expr/variable.go
@@ -11,7 +11,7 @@ type Variable struct {
 	VarName  node.Node
 }
 
-func NewVariable(VarName node.Node) node.Node {
+func NewVariable(VarName node.Node) *Variable {
 	return &Variable{
 		nil,
 		nil,
diff --git a/node/expr/yield.go b/node/expr/yield.go
index add0f4d..2acdb62 100644
--- a/node/expr/yield.go
+++ b/node/expr/yield.go
@@ -12,7 +12,7 @@ type Yield struct {
 	Value    node.Node
 }
 
-func NewYield(Key node.Node, Value node.Node) node.Node {
+func NewYield(Key node.Node, Value node.Node) *Yield {
 	return &Yield{
 		nil,
 		nil,
diff --git a/node/expr/yield_from.go b/node/expr/yield_from.go
index 19efee7..b4a905b 100644
--- a/node/expr/yield_from.go
+++ b/node/expr/yield_from.go
@@ -11,7 +11,7 @@ type YieldFrom struct {
 	Expr     node.Node
 }
 
-func NewYieldFrom(Expression node.Node) node.Node {
+func NewYieldFrom(Expression node.Node) *YieldFrom {
 	return &YieldFrom{
 		nil,
 		nil,
diff --git a/node/identifier.go b/node/identifier.go
index 533e74d..d807fc3 100644
--- a/node/identifier.go
+++ b/node/identifier.go
@@ -8,7 +8,7 @@ type Identifier struct {
 	Value    string
 }
 
-func NewIdentifier(Value string) Node {
+func NewIdentifier(Value string) *Identifier {
 	return &Identifier{
 		nil,
 		nil,
diff --git a/node/name/fully_qualified.go b/node/name/fully_qualified.go
index b12a479..1eddde1 100644
--- a/node/name/fully_qualified.go
+++ b/node/name/fully_qualified.go
@@ -8,7 +8,7 @@ type FullyQualified struct {
 	Name
 }
 
-func NewFullyQualified(Parts []node.Node) node.Node {
+func NewFullyQualified(Parts []node.Node) *FullyQualified {
 	return &FullyQualified{
 		Name{
 			nil,
diff --git a/node/name/name.go b/node/name/name.go
index 3c8d5b2..db7a2cc 100644
--- a/node/name/name.go
+++ b/node/name/name.go
@@ -11,7 +11,7 @@ type Name struct {
 	Parts    []node.Node
 }
 
-func NewName(Parts []node.Node) node.Node {
+func NewName(Parts []node.Node) *Name {
 	return &Name{
 		nil,
 		nil,
diff --git a/node/name/name_part.go b/node/name/name_part.go
index 9ce00c9..e2f481b 100644
--- a/node/name/name_part.go
+++ b/node/name/name_part.go
@@ -11,7 +11,7 @@ type NamePart struct {
 	Value    string
 }
 
-func NewNamePart(Value string) node.Node {
+func NewNamePart(Value string) *NamePart {
 	return &NamePart{
 		nil,
 		nil,
diff --git a/node/name/relative.go b/node/name/relative.go
index 72d50c4..720307d 100644
--- a/node/name/relative.go
+++ b/node/name/relative.go
@@ -8,7 +8,7 @@ type Relative struct {
 	Name
 }
 
-func NewRelative(Parts []node.Node) node.Node {
+func NewRelative(Parts []node.Node) *Relative {
 	return &Relative{
 		Name{
 			nil,
diff --git a/node/nullable.go b/node/nullable.go
index 7dc8355..c1eccf4 100644
--- a/node/nullable.go
+++ b/node/nullable.go
@@ -8,7 +8,7 @@ type Nullable struct {
 	Expr     Node
 }
 
-func NewNullable(Expression Node) Node {
+func NewNullable(Expression Node) *Nullable {
 	return &Nullable{
 		nil,
 		nil,
diff --git a/node/parameter.go b/node/parameter.go
index 65cfe0e..f40922d 100644
--- a/node/parameter.go
+++ b/node/parameter.go
@@ -12,7 +12,7 @@ type Parameter struct {
 	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) *Parameter {
 	return &Parameter{
 		nil,
 		nil,
diff --git a/node/scalar/dnumber.go b/node/scalar/dnumber.go
index b2696cd..8753126 100644
--- a/node/scalar/dnumber.go
+++ b/node/scalar/dnumber.go
@@ -11,7 +11,7 @@ type Dnumber struct {
 	Value    string
 }
 
-func NewDnumber(Value string) node.Node {
+func NewDnumber(Value string) *Dnumber {
 	return &Dnumber{
 		nil,
 		nil,
diff --git a/node/scalar/encapsed.go b/node/scalar/encapsed.go
index 693f195..b6ab72d 100644
--- a/node/scalar/encapsed.go
+++ b/node/scalar/encapsed.go
@@ -11,7 +11,7 @@ type Encapsed struct {
 	Parts    []node.Node
 }
 
-func NewEncapsed(Parts []node.Node) node.Node {
+func NewEncapsed(Parts []node.Node) *Encapsed {
 	return &Encapsed{
 		nil,
 		nil,
diff --git a/node/scalar/encapsed_string_part.go b/node/scalar/encapsed_string_part.go
index c17af13..8bd6d37 100644
--- a/node/scalar/encapsed_string_part.go
+++ b/node/scalar/encapsed_string_part.go
@@ -11,7 +11,7 @@ type EncapsedStringPart struct {
 	Value    string
 }
 
-func NewEncapsedStringPart(Value string) node.Node {
+func NewEncapsedStringPart(Value string) *EncapsedStringPart {
 	return &EncapsedStringPart{
 		nil,
 		nil,
diff --git a/node/scalar/lnumber.go b/node/scalar/lnumber.go
index cdd06f3..1de4632 100644
--- a/node/scalar/lnumber.go
+++ b/node/scalar/lnumber.go
@@ -11,7 +11,7 @@ type Lnumber struct {
 	Value    string
 }
 
-func NewLnumber(Value string) node.Node {
+func NewLnumber(Value string) *Lnumber {
 	return &Lnumber{
 		nil,
 		nil,
diff --git a/node/scalar/magic_constant.go b/node/scalar/magic_constant.go
index a9d1671..cb9b813 100644
--- a/node/scalar/magic_constant.go
+++ b/node/scalar/magic_constant.go
@@ -11,7 +11,7 @@ type MagicConstant struct {
 	Value    string
 }
 
-func NewMagicConstant(Value string) node.Node {
+func NewMagicConstant(Value string) *MagicConstant {
 	return &MagicConstant{
 		nil,
 		nil,
diff --git a/node/scalar/string.go b/node/scalar/string.go
index 79dff54..f2facea 100644
--- a/node/scalar/string.go
+++ b/node/scalar/string.go
@@ -11,7 +11,7 @@ type String struct {
 	Value    string
 }
 
-func NewString(Value string) node.Node {
+func NewString(Value string) *String {
 	return &String{
 		nil,
 		nil,
diff --git a/node/stmt/alt_else.go b/node/stmt/alt_else.go
index a3b390d..cc9515f 100644
--- a/node/stmt/alt_else.go
+++ b/node/stmt/alt_else.go
@@ -11,7 +11,7 @@ type AltElse struct {
 	Stmt     node.Node
 }
 
-func NewAltElse(Stmt node.Node) node.Node {
+func NewAltElse(Stmt node.Node) *AltElse {
 	return &AltElse{
 		nil,
 		nil,
diff --git a/node/stmt/alt_else_if.go b/node/stmt/alt_else_if.go
index b516b26..521590e 100644
--- a/node/stmt/alt_else_if.go
+++ b/node/stmt/alt_else_if.go
@@ -12,7 +12,7 @@ type AltElseIf struct {
 	Stmt     node.Node
 }
 
-func NewAltElseIf(Cond node.Node, Stmt node.Node) node.Node {
+func NewAltElseIf(Cond node.Node, Stmt node.Node) *AltElseIf {
 	return &AltElseIf{
 		nil,
 		nil,
diff --git a/node/stmt/alt_if.go b/node/stmt/alt_if.go
index 55604ad..18b8c7e 100644
--- a/node/stmt/alt_if.go
+++ b/node/stmt/alt_if.go
@@ -14,7 +14,7 @@ type AltIf struct {
 	_else    node.Node
 }
 
-func NewAltIf(Cond node.Node, Stmt node.Node) node.Node {
+func NewAltIf(Cond node.Node, Stmt node.Node) *AltIf {
 	return &AltIf{
 		nil,
 		nil,
diff --git a/node/stmt/break.go b/node/stmt/break.go
index 9313dfb..1a32ebc 100644
--- a/node/stmt/break.go
+++ b/node/stmt/break.go
@@ -11,7 +11,7 @@ type Break struct {
 	Expr     node.Node
 }
 
-func NewBreak(Expr node.Node) node.Node {
+func NewBreak(Expr node.Node) *Break {
 	return &Break{
 		nil,
 		nil,
diff --git a/node/stmt/case.go b/node/stmt/case.go
index 0dcfe77..abae93d 100644
--- a/node/stmt/case.go
+++ b/node/stmt/case.go
@@ -12,7 +12,7 @@ type Case struct {
 	Stmts    []node.Node
 }
 
-func NewCase(Cond node.Node, Stmts []node.Node) node.Node {
+func NewCase(Cond node.Node, Stmts []node.Node) *Case {
 	return &Case{
 		nil,
 		nil,
diff --git a/node/stmt/catch.go b/node/stmt/catch.go
index cfe5e5e..527a737 100644
--- a/node/stmt/catch.go
+++ b/node/stmt/catch.go
@@ -13,7 +13,7 @@ type Catch struct {
 	Stmts    []node.Node
 }
 
-func NewCatch(Types []node.Node, Variable node.Node, Stmts []node.Node) node.Node {
+func NewCatch(Types []node.Node, Variable node.Node, Stmts []node.Node) *Catch {
 	return &Catch{
 		nil,
 		nil,
diff --git a/node/stmt/class.go b/node/stmt/class.go
index 1fafb67..28ddd18 100644
--- a/node/stmt/class.go
+++ b/node/stmt/class.go
@@ -17,7 +17,7 @@ type Class struct {
 	Stmts         []node.Node
 }
 
-func NewClass(ClassName node.Node, Modifiers []node.Node, args []node.Node, Extends node.Node, Implements []node.Node, Stmts []node.Node, PhpDocComment string) node.Node {
+func NewClass(ClassName node.Node, Modifiers []node.Node, args []node.Node, Extends node.Node, Implements []node.Node, Stmts []node.Node, PhpDocComment string) *Class {
 	return &Class{
 		nil,
 		nil,
diff --git a/node/stmt/class_const_list.go b/node/stmt/class_const_list.go
index faa3aef..8be4d74 100644
--- a/node/stmt/class_const_list.go
+++ b/node/stmt/class_const_list.go
@@ -12,7 +12,7 @@ type ClassConstList struct {
 	Consts    []node.Node
 }
 
-func NewClassConstList(Modifiers []node.Node, Consts []node.Node) node.Node {
+func NewClassConstList(Modifiers []node.Node, Consts []node.Node) *ClassConstList {
 	return &ClassConstList{
 		nil,
 		nil,
diff --git a/node/stmt/class_method.go b/node/stmt/class_method.go
index a48b43e..ed38667 100644
--- a/node/stmt/class_method.go
+++ b/node/stmt/class_method.go
@@ -17,7 +17,7 @@ type ClassMethod struct {
 	Stmts         []node.Node
 }
 
-func NewClassMethod(MethodName node.Node, Modifiers []node.Node, ReturnsRef bool, Params []node.Node, ReturnType node.Node, Stmts []node.Node, PhpDocComment string) node.Node {
+func NewClassMethod(MethodName node.Node, Modifiers []node.Node, ReturnsRef bool, Params []node.Node, ReturnType node.Node, Stmts []node.Node, PhpDocComment string) *ClassMethod {
 	return &ClassMethod{
 		nil,
 		nil,
diff --git a/node/stmt/const_list.go b/node/stmt/const_list.go
index 61144ab..6e50e9f 100644
--- a/node/stmt/const_list.go
+++ b/node/stmt/const_list.go
@@ -11,7 +11,7 @@ type ConstList struct {
 	Consts   []node.Node
 }
 
-func NewConstList(Consts []node.Node) node.Node {
+func NewConstList(Consts []node.Node) *ConstList {
 	return &ConstList{
 		nil,
 		nil,
diff --git a/node/stmt/constant.go b/node/stmt/constant.go
index 77cdb61..8780f39 100644
--- a/node/stmt/constant.go
+++ b/node/stmt/constant.go
@@ -13,7 +13,7 @@ type Constant struct {
 	Expr          node.Node
 }
 
-func NewConstant(ConstantName node.Node, Expr node.Node, PhpDocComment string) node.Node {
+func NewConstant(ConstantName node.Node, Expr node.Node, PhpDocComment string) *Constant {
 	return &Constant{
 		nil,
 		nil,
diff --git a/node/stmt/continue.go b/node/stmt/continue.go
index 773084d..9774525 100644
--- a/node/stmt/continue.go
+++ b/node/stmt/continue.go
@@ -11,7 +11,7 @@ type Continue struct {
 	Expr     node.Node
 }
 
-func NewContinue(Expr node.Node) node.Node {
+func NewContinue(Expr node.Node) *Continue {
 	return &Continue{
 		nil,
 		nil,
diff --git a/node/stmt/declare.go b/node/stmt/declare.go
index 828cd7d..df619cd 100644
--- a/node/stmt/declare.go
+++ b/node/stmt/declare.go
@@ -12,7 +12,7 @@ type Declare struct {
 	Stmt     node.Node
 }
 
-func NewDeclare(Consts []node.Node, Stmt node.Node) node.Node {
+func NewDeclare(Consts []node.Node, Stmt node.Node) *Declare {
 	return &Declare{
 		nil,
 		nil,
diff --git a/node/stmt/default.go b/node/stmt/default.go
index 7a2d629..6983f40 100644
--- a/node/stmt/default.go
+++ b/node/stmt/default.go
@@ -11,7 +11,7 @@ type Default struct {
 	Stmts    []node.Node
 }
 
-func NewDefault(Stmts []node.Node) node.Node {
+func NewDefault(Stmts []node.Node) *Default {
 	return &Default{
 		nil,
 		nil,
diff --git a/node/stmt/do.go b/node/stmt/do.go
index 8f4535f..6c33134 100644
--- a/node/stmt/do.go
+++ b/node/stmt/do.go
@@ -12,7 +12,7 @@ type Do struct {
 	Cond     node.Node
 }
 
-func NewDo(Stmt node.Node, Cond node.Node) node.Node {
+func NewDo(Stmt node.Node, Cond node.Node) *Do {
 	return &Do{
 		nil,
 		nil,
diff --git a/node/stmt/echo.go b/node/stmt/echo.go
index 5a6054d..4f457d3 100644
--- a/node/stmt/echo.go
+++ b/node/stmt/echo.go
@@ -11,7 +11,7 @@ type Echo struct {
 	Exprs    []node.Node
 }
 
-func NewEcho(Exprs []node.Node) node.Node {
+func NewEcho(Exprs []node.Node) *Echo {
 	return &Echo{
 		nil,
 		nil,
diff --git a/node/stmt/else.go b/node/stmt/else.go
index fec37bc..17ef2b3 100644
--- a/node/stmt/else.go
+++ b/node/stmt/else.go
@@ -11,7 +11,7 @@ type Else struct {
 	Stmt     node.Node
 }
 
-func NewElse(Stmt node.Node) node.Node {
+func NewElse(Stmt node.Node) *Else {
 	return &Else{
 		nil,
 		nil,
diff --git a/node/stmt/else_if.go b/node/stmt/else_if.go
index 6e06e0e..3a4472e 100644
--- a/node/stmt/else_if.go
+++ b/node/stmt/else_if.go
@@ -12,7 +12,7 @@ type ElseIf struct {
 	Stmt     node.Node
 }
 
-func NewElseIf(Cond node.Node, Stmt node.Node) node.Node {
+func NewElseIf(Cond node.Node, Stmt node.Node) *ElseIf {
 	return &ElseIf{
 		nil,
 		nil,
diff --git a/node/stmt/expression.go b/node/stmt/expression.go
index 93f6d37..9afdad1 100644
--- a/node/stmt/expression.go
+++ b/node/stmt/expression.go
@@ -11,7 +11,7 @@ type Expression struct {
 	Expr     node.Node
 }
 
-func NewExpression(Expr node.Node) node.Node {
+func NewExpression(Expr node.Node) *Expression {
 	return &Expression{
 		nil,
 		nil,
diff --git a/node/stmt/finally.go b/node/stmt/finally.go
index d2a5df1..cec047f 100644
--- a/node/stmt/finally.go
+++ b/node/stmt/finally.go
@@ -11,7 +11,7 @@ type Finally struct {
 	Stmts    []node.Node
 }
 
-func NewFinally(Stmts []node.Node) node.Node {
+func NewFinally(Stmts []node.Node) *Finally {
 	return &Finally{
 		nil,
 		nil,
diff --git a/node/stmt/for.go b/node/stmt/for.go
index f6dd0ff..13f8cef 100644
--- a/node/stmt/for.go
+++ b/node/stmt/for.go
@@ -14,7 +14,7 @@ type For struct {
 	Stmt     node.Node
 }
 
-func NewFor(Init []node.Node, Cond []node.Node, Loop []node.Node, Stmt node.Node) node.Node {
+func NewFor(Init []node.Node, Cond []node.Node, Loop []node.Node, Stmt node.Node) *For {
 	return &For{
 		nil,
 		nil,
diff --git a/node/stmt/foreach.go b/node/stmt/foreach.go
index d328438..a86edcb 100644
--- a/node/stmt/foreach.go
+++ b/node/stmt/foreach.go
@@ -15,7 +15,7 @@ type Foreach struct {
 	Stmt     node.Node
 }
 
-func NewForeach(Expr node.Node, Key node.Node, Variable node.Node, Stmt node.Node, ByRef bool) node.Node {
+func NewForeach(Expr node.Node, Key node.Node, Variable node.Node, Stmt node.Node, ByRef bool) *Foreach {
 	return &Foreach{
 		nil,
 		nil,
diff --git a/node/stmt/function.go b/node/stmt/function.go
index 83bee35..d683b1b 100644
--- a/node/stmt/function.go
+++ b/node/stmt/function.go
@@ -16,7 +16,7 @@ type Function struct {
 	Stmts         []node.Node
 }
 
-func NewFunction(FunctionName node.Node, ReturnsRef bool, Params []node.Node, ReturnType node.Node, Stmts []node.Node, PhpDocComment string) node.Node {
+func NewFunction(FunctionName node.Node, ReturnsRef bool, Params []node.Node, ReturnType node.Node, Stmts []node.Node, PhpDocComment string) *Function {
 	return &Function{
 		nil,
 		nil,
diff --git a/node/stmt/global.go b/node/stmt/global.go
index 90bb138..3e21451 100644
--- a/node/stmt/global.go
+++ b/node/stmt/global.go
@@ -11,7 +11,7 @@ type Global struct {
 	Vars     []node.Node
 }
 
-func NewGlobal(Vars []node.Node) node.Node {
+func NewGlobal(Vars []node.Node) *Global {
 	return &Global{
 		nil,
 		nil,
diff --git a/node/stmt/goto.go b/node/stmt/goto.go
index 81ac98e..a203fdf 100644
--- a/node/stmt/goto.go
+++ b/node/stmt/goto.go
@@ -11,7 +11,7 @@ type Goto struct {
 	Label    node.Node
 }
 
-func NewGoto(Label node.Node) node.Node {
+func NewGoto(Label node.Node) *Goto {
 	return &Goto{
 		nil,
 		nil,
diff --git a/node/stmt/group_use.go b/node/stmt/group_use.go
index 628b392..988aca5 100644
--- a/node/stmt/group_use.go
+++ b/node/stmt/group_use.go
@@ -13,7 +13,7 @@ type GroupUse struct {
 	UseList  []node.Node
 }
 
-func NewGroupUse(UseType node.Node, pRefix node.Node, UseList []node.Node) node.Node {
+func NewGroupUse(UseType node.Node, pRefix node.Node, UseList []node.Node) *GroupUse {
 	return &GroupUse{
 		nil,
 		nil,
diff --git a/node/stmt/halt_compiler.go b/node/stmt/halt_compiler.go
index 7e7f259..c52cda5 100644
--- a/node/stmt/halt_compiler.go
+++ b/node/stmt/halt_compiler.go
@@ -10,7 +10,7 @@ type HaltCompiler struct {
 	comments *[]comment.Comment
 }
 
-func NewHaltCompiler() node.Node {
+func NewHaltCompiler() *HaltCompiler {
 	return &HaltCompiler{
 		nil,
 		nil,
diff --git a/node/stmt/if.go b/node/stmt/if.go
index 90668e7..f0d5130 100644
--- a/node/stmt/if.go
+++ b/node/stmt/if.go
@@ -14,7 +14,7 @@ type If struct {
 	_else    node.Node
 }
 
-func NewIf(Cond node.Node, Stmt node.Node) node.Node {
+func NewIf(Cond node.Node, Stmt node.Node) *If {
 	return &If{
 		nil,
 		nil,
diff --git a/node/stmt/inline_html.go b/node/stmt/inline_html.go
index 38f2f42..f1b471c 100644
--- a/node/stmt/inline_html.go
+++ b/node/stmt/inline_html.go
@@ -11,7 +11,7 @@ type InlineHtml struct {
 	Value    string
 }
 
-func NewInlineHtml(Value string) node.Node {
+func NewInlineHtml(Value string) *InlineHtml {
 	return &InlineHtml{
 		nil,
 		nil,
diff --git a/node/stmt/interface.go b/node/stmt/interface.go
index 4f5b1c0..b951f02 100644
--- a/node/stmt/interface.go
+++ b/node/stmt/interface.go
@@ -14,7 +14,7 @@ type Interface struct {
 	Stmts         []node.Node
 }
 
-func NewInterface(InterfaceName node.Node, Extends []node.Node, Stmts []node.Node, PhpDocComment string) node.Node {
+func NewInterface(InterfaceName node.Node, Extends []node.Node, Stmts []node.Node, PhpDocComment string) *Interface {
 	return &Interface{
 		nil,
 		nil,
diff --git a/node/stmt/label.go b/node/stmt/label.go
index ee70300..86d5961 100644
--- a/node/stmt/label.go
+++ b/node/stmt/label.go
@@ -11,7 +11,7 @@ type Label struct {
 	LabelName node.Node
 }
 
-func NewLabel(LabelName node.Node) node.Node {
+func NewLabel(LabelName node.Node) *Label {
 	return &Label{
 		nil,
 		nil,
diff --git a/node/stmt/namespace.go b/node/stmt/namespace.go
index 57b7d40..8593d74 100644
--- a/node/stmt/namespace.go
+++ b/node/stmt/namespace.go
@@ -12,7 +12,7 @@ type Namespace struct {
 	Stmts         []node.Node
 }
 
-func NewNamespace(NamespaceName node.Node, Stmts []node.Node) node.Node {
+func NewNamespace(NamespaceName node.Node, Stmts []node.Node) *Namespace {
 	return &Namespace{
 		nil,
 		nil,
diff --git a/node/stmt/nop.go b/node/stmt/nop.go
index d173ab5..1f25173 100644
--- a/node/stmt/nop.go
+++ b/node/stmt/nop.go
@@ -10,7 +10,7 @@ type Nop struct {
 	comments *[]comment.Comment
 }
 
-func NewNop() node.Node {
+func NewNop() *Nop {
 	return &Nop{
 		nil,
 		nil,
diff --git a/node/stmt/property.go b/node/stmt/property.go
index 1097b71..999a8aa 100644
--- a/node/stmt/property.go
+++ b/node/stmt/property.go
@@ -13,7 +13,7 @@ type Property struct {
 	Expr          node.Node
 }
 
-func NewProperty(Variable node.Node, Expr node.Node, PhpDocComment string) node.Node {
+func NewProperty(Variable node.Node, Expr node.Node, PhpDocComment string) *Property {
 	return &Property{
 		nil,
 		nil,
diff --git a/node/stmt/property_list.go b/node/stmt/property_list.go
index b00ac7c..de199f8 100644
--- a/node/stmt/property_list.go
+++ b/node/stmt/property_list.go
@@ -12,7 +12,7 @@ type PropertyList struct {
 	Properties []node.Node
 }
 
-func NewPropertyList(Modifiers []node.Node, Properties []node.Node) node.Node {
+func NewPropertyList(Modifiers []node.Node, Properties []node.Node) *PropertyList {
 	return &PropertyList{
 		nil,
 		nil,
diff --git a/node/stmt/return.go b/node/stmt/return.go
index 432cffe..3b2b70a 100644
--- a/node/stmt/return.go
+++ b/node/stmt/return.go
@@ -11,7 +11,7 @@ type Return struct {
 	Expr     node.Node
 }
 
-func NewReturn(Expr node.Node) node.Node {
+func NewReturn(Expr node.Node) *Return {
 	return &Return{
 		nil,
 		nil,
diff --git a/node/stmt/static.go b/node/stmt/static.go
index 4db90e0..501352a 100644
--- a/node/stmt/static.go
+++ b/node/stmt/static.go
@@ -11,7 +11,7 @@ type Static struct {
 	Vars     []node.Node
 }
 
-func NewStatic(Vars []node.Node) node.Node {
+func NewStatic(Vars []node.Node) *Static {
 	return &Static{
 		nil,
 		nil,
diff --git a/node/stmt/static_var.go b/node/stmt/static_var.go
index 14de22c..201d186 100644
--- a/node/stmt/static_var.go
+++ b/node/stmt/static_var.go
@@ -12,7 +12,7 @@ type StaticVar struct {
 	Expr     node.Node
 }
 
-func NewStaticVar(Variable node.Node, Expr node.Node) node.Node {
+func NewStaticVar(Variable node.Node, Expr node.Node) *StaticVar {
 	return &StaticVar{
 		nil,
 		nil,
diff --git a/node/stmt/stmt_list.go b/node/stmt/stmt_list.go
index d4f1d16..a25685b 100644
--- a/node/stmt/stmt_list.go
+++ b/node/stmt/stmt_list.go
@@ -11,7 +11,7 @@ type StmtList struct {
 	Stmts    []node.Node
 }
 
-func NewStmtList(Stmts []node.Node) node.Node {
+func NewStmtList(Stmts []node.Node) *StmtList {
 	return &StmtList{
 		nil,
 		nil,
diff --git a/node/stmt/switch.go b/node/stmt/switch.go
index 71e1e6a..782b3d6 100644
--- a/node/stmt/switch.go
+++ b/node/stmt/switch.go
@@ -14,7 +14,7 @@ type Switch struct {
 	cases    []node.Node
 }
 
-func NewSwitch(token token.Token, Cond node.Node, cases []node.Node) node.Node {
+func NewSwitch(token token.Token, Cond node.Node, cases []node.Node) *Switch {
 	return &Switch{
 		nil,
 		nil,
diff --git a/node/stmt/throw.go b/node/stmt/throw.go
index 9b0db9b..13b7fb0 100644
--- a/node/stmt/throw.go
+++ b/node/stmt/throw.go
@@ -11,7 +11,7 @@ type Throw struct {
 	Expr     node.Node
 }
 
-func NewThrow(Expr node.Node) node.Node {
+func NewThrow(Expr node.Node) *Throw {
 	return &Throw{
 		nil,
 		nil,
diff --git a/node/stmt/trait.go b/node/stmt/trait.go
index ae6c927..496b08a 100644
--- a/node/stmt/trait.go
+++ b/node/stmt/trait.go
@@ -13,7 +13,7 @@ type Trait struct {
 	Stmts         []node.Node
 }
 
-func NewTrait(TraitName node.Node, Stmts []node.Node, PhpDocComment string) node.Node {
+func NewTrait(TraitName node.Node, Stmts []node.Node, PhpDocComment string) *Trait {
 	return &Trait{
 		nil,
 		nil,
diff --git a/node/stmt/trait_method_ref.go b/node/stmt/trait_method_ref.go
index 7157dfb..da303e2 100644
--- a/node/stmt/trait_method_ref.go
+++ b/node/stmt/trait_method_ref.go
@@ -12,7 +12,7 @@ type TraitMethodRef struct {
 	Method   node.Node
 }
 
-func NewTraitMethodRef(Trait node.Node, Method node.Node) node.Node {
+func NewTraitMethodRef(Trait node.Node, Method node.Node) *TraitMethodRef {
 	return &TraitMethodRef{
 		nil,
 		nil,
diff --git a/node/stmt/trait_use.go b/node/stmt/trait_use.go
index cc955c4..d611fd5 100644
--- a/node/stmt/trait_use.go
+++ b/node/stmt/trait_use.go
@@ -12,7 +12,7 @@ type TraitUse struct {
 	Adaptations []node.Node
 }
 
-func NewTraitUse(Traits []node.Node, Adaptations []node.Node) node.Node {
+func NewTraitUse(Traits []node.Node, Adaptations []node.Node) *TraitUse {
 	return &TraitUse{
 		nil,
 		nil,
diff --git a/node/stmt/trait_use_alias.go b/node/stmt/trait_use_alias.go
index 6ad9e24..306f78f 100644
--- a/node/stmt/trait_use_alias.go
+++ b/node/stmt/trait_use_alias.go
@@ -13,7 +13,7 @@ type TraitUseAlias struct {
 	Alias    node.Node
 }
 
-func NewTraitUseAlias(Ref node.Node, Modifier node.Node, Alias node.Node) node.Node {
+func NewTraitUseAlias(Ref node.Node, Modifier node.Node, Alias node.Node) *TraitUseAlias {
 	return &TraitUseAlias{
 		nil,
 		nil,
diff --git a/node/stmt/trait_use_precedence.go b/node/stmt/trait_use_precedence.go
index dbe9025..fe9caea 100644
--- a/node/stmt/trait_use_precedence.go
+++ b/node/stmt/trait_use_precedence.go
@@ -12,7 +12,7 @@ type TraitUsePrecedence struct {
 	Insteadof node.Node
 }
 
-func NewTraitUsePrecedence(Ref node.Node, Insteadof node.Node) node.Node {
+func NewTraitUsePrecedence(Ref node.Node, Insteadof node.Node) *TraitUsePrecedence {
 	return &TraitUsePrecedence{
 		nil,
 		nil,
diff --git a/node/stmt/try.go b/node/stmt/try.go
index b741387..046829b 100644
--- a/node/stmt/try.go
+++ b/node/stmt/try.go
@@ -13,7 +13,7 @@ type Try struct {
 	Finally  node.Node
 }
 
-func NewTry(Stmts []node.Node, Catches []node.Node, Finally node.Node) node.Node {
+func NewTry(Stmts []node.Node, Catches []node.Node, Finally node.Node) *Try {
 	return &Try{
 		nil,
 		nil,
diff --git a/node/stmt/unset.go b/node/stmt/unset.go
index f820002..b231d46 100644
--- a/node/stmt/unset.go
+++ b/node/stmt/unset.go
@@ -11,7 +11,7 @@ type Unset struct {
 	Vars     []node.Node
 }
 
-func NewUnset(Vars []node.Node) node.Node {
+func NewUnset(Vars []node.Node) *Unset {
 	return &Unset{
 		nil,
 		nil,
diff --git a/node/stmt/use.go b/node/stmt/use.go
index eb0ce41..455504d 100644
--- a/node/stmt/use.go
+++ b/node/stmt/use.go
@@ -13,7 +13,7 @@ type Use struct {
 	Alias    node.Node
 }
 
-func NewUse(UseType node.Node, use node.Node, Alias node.Node) node.Node {
+func NewUse(UseType node.Node, use node.Node, Alias node.Node) *Use {
 	return &Use{
 		nil,
 		nil,
diff --git a/node/stmt/use_list.go b/node/stmt/use_list.go
index 2d4ddb6..a6400e5 100644
--- a/node/stmt/use_list.go
+++ b/node/stmt/use_list.go
@@ -12,7 +12,7 @@ type UseList struct {
 	Uses     []node.Node
 }
 
-func NewUseList(UseType node.Node, Uses []node.Node) node.Node {
+func NewUseList(UseType node.Node, Uses []node.Node) *UseList {
 	return &UseList{
 		nil,
 		nil,
diff --git a/node/stmt/while.go b/node/stmt/while.go
index 4c9f8fd..cd7e66e 100644
--- a/node/stmt/while.go
+++ b/node/stmt/while.go
@@ -14,7 +14,7 @@ type While struct {
 	Stmt     node.Node
 }
 
-func NewWhile(Token token.Token, Cond node.Node, Stmt node.Node) node.Node {
+func NewWhile(Token token.Token, Cond node.Node, Stmt node.Node) *While {
 	return &While{
 		nil,
 		nil,
diff --git a/parser/parser.go b/parser/parser.go
index 3361799..3f2bbd2 100644
--- a/parser/parser.go
+++ b/parser/parser.go
@@ -20,7 +20,7 @@ import (
 	"strings"
 )
 
-var rootnode = stmt.NewStmtList([]node.Node{})
+var rootnode node.Node
 
 func Parse(src io.Reader, fName string) node.Node {
 	yyDebug = 0
diff --git a/parser/parser.y b/parser/parser.y
index 0c7dc80..db43d24 100644
--- a/parser/parser.y
+++ b/parser/parser.y
@@ -17,7 +17,7 @@ import (
     "github.com/z7zmey/php-parser/comment"
 )
 
-var rootnode = stmt.NewStmtList([]node.Node{})
+var rootnode node.Node
 
 func Parse(src io.Reader, fName string) node.Node {
     yyDebug        = 0