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|
package ast
import (
"bytes"
"fmt"
)
type Node struct {
Parent *Node
Children []*Node
Value interface{}
Kind Kind
}
func NewNode(k Kind, v interface{}, ch ...*Node) *Node {
n := &Node{
Kind: k,
Value: v,
}
for _, c := range ch {
Insert(n, c)
}
return n
}
func (a *Node) Equal(b *Node) bool {
if a.Kind != b.Kind {
return false
}
if a.Value != b.Value {
return false
}
if len(a.Children) != len(b.Children) {
return false
}
for i, c := range a.Children {
if !c.Equal(b.Children[i]) {
return false
}
}
return true
}
func (a *Node) String() string {
var buf bytes.Buffer
buf.WriteString(a.Kind.String())
if a.Value != nil {
buf.WriteString(" =")
buf.WriteString(fmt.Sprintf("%v", a.Value))
}
if len(a.Children) > 0 {
buf.WriteString(" [")
for i, c := range a.Children {
if i > 0 {
buf.WriteString(", ")
}
buf.WriteString(c.String())
}
buf.WriteString("]")
}
return buf.String()
}
func Insert(parent *Node, children ...*Node) {
parent.Children = append(parent.Children, children...)
for _, ch := range children {
ch.Parent = parent
}
}
type List struct {
Not bool
Chars string
}
type Range struct {
Not bool
Lo, Hi rune
}
type Text struct {
Text string
}
type Kind int
const (
KindNothing Kind = iota
KindPattern
KindList
KindRange
KindText
KindAny
KindSuper
KindSingle
KindAnyOf
)
func (k Kind) String() string {
switch k {
case KindNothing:
return "Nothing"
case KindPattern:
return "Pattern"
case KindList:
return "List"
case KindRange:
return "Range"
case KindText:
return "Text"
case KindAny:
return "Any"
case KindSuper:
return "Super"
case KindSingle:
return "Single"
case KindAnyOf:
return "AnyOf"
default:
return ""
}
}
|
