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package parser
import "github.com/gnolang/parscan/scanner"
type Node struct {
Child []*Node // sub-tree nodes
scanner.Token // token at origin of the node
Kind // Node kind, depends on the language spec
unary bool // TODO(marc): get rid of it.
}
// TODO: remove it in favor of Walk2
func (n *Node) Walk(in, out func(*Node) bool) (stop bool) {
if in != nil && !in(n) {
return true
}
for _, child := range n.Child {
if child.Walk(in, out) {
return
}
}
if out != nil {
stop = !out(n)
}
return
}
// Idem to walk, but also propagates the ancestor of visited node and child index.
func (n *Node) Walk2(a *Node, i int, in, out func(*Node, *Node, int) bool) (stop bool) {
if in != nil && !in(n, a, i) {
return true
}
for j, child := range n.Child {
if child.Walk2(n, j, in, out) {
return
}
}
if out != nil {
stop = !out(n, a, i)
}
return
}
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