Move ast and parser out of internal

ast/ast.go

@@ -0,0 +1,190 @@
+package ast
+
+import "fmt"
+
+func PosError(n Node, filename, format string, v ...any) error {
+	return fmt.Errorf(filename+":"+n.Pos().String()+": "+format, v...)
+}
+
+type Node interface {
+	Pos() Position
+}
+
+type Position struct {
+	Line int
+	Col  int
+}
+
+func (p Position) String() string {
+	return fmt.Sprintf("%d:%d", p.Line, p.Col)
+}
+
+type Tag struct {
+	Name     Ident
+	Params   []Node
+	HasBody  bool
+	Position Position
+}
+
+func (t Tag) Pos() Position {
+	return t.Position
+}
+
+type ExprTag struct {
+	Value    Node
+	Position Position
+}
+
+func (et ExprTag) Pos() Position {
+	return et.Position
+}
+
+type EndTag struct {
+	Name     Ident
+	Position Position
+}
+
+func (et EndTag) Pos() Position {
+	return et.Position
+}
+
+type Text struct {
+	Data     []byte
+	Position Position
+}
+
+func (t Text) Pos() Position {
+	return t.Position
+}
+
+type Value struct {
+	Node
+	Not bool
+}
+
+type Expr struct {
+	First    Node
+	Operator Operator
+	Rest     []Expr
+	Position Position
+}
+
+func (e Expr) Pos() Position {
+	return e.Position
+}
+
+type FuncCall struct {
+	Name     Ident
+	Params   []Node
+	Position Position
+}
+
+func (fc FuncCall) Pos() Position {
+	return fc.Position
+}
+
+type MethodCall struct {
+	Value    Node
+	Name     Ident
+	Params   []Node
+	Position Position
+}
+
+func (mc MethodCall) Pos() Position {
+	return mc.Position
+}
+
+type FieldAccess struct {
+	Value    Node
+	Name     Ident
+	Position Position
+}
+
+func (fa FieldAccess) Pos() Position {
+	return fa.Position
+}
+
+type Index struct {
+	Value    Node
+	Index    Node
+	Position Position
+}
+
+func (i Index) Pos() Position {
+	return i.Position
+}
+
+type Ident struct {
+	Value    string
+	Position Position
+}
+
+func (id Ident) Pos() Position {
+	return id.Position
+}
+
+type String struct {
+	Value    string
+	Position Position
+}
+
+func (s String) Pos() Position {
+	return s.Position
+}
+
+type Float struct {
+	Value    float64
+	Position Position
+}
+
+func (f Float) Pos() Position {
+	return f.Position
+}
+
+type Integer struct {
+	Value    int64
+	Position Position
+}
+
+func (i Integer) Pos() Position {
+	return i.Position
+}
+
+type Bool struct {
+	Value    bool
+	Position Position
+}
+
+func (b Bool) Pos() Position {
+	return b.Position
+}
+
+type Operator struct {
+	Value    string
+	Position Position
+}
+
+func (op Operator) Pos() Position {
+	return op.Position
+}
+
+type Ternary struct {
+	Condition Node
+	IfTrue    Node
+	Else      Node
+	Position  Position
+}
+
+func (t Ternary) Pos() Position {
+	return t.Position
+}
+
+type VariableOr struct {
+	Variable Ident
+	Or       Node
+	Position Position
+}
+
+func (vo VariableOr) Pos() Position {
+	return vo.Position
+}