| 1 | export default function walk(ast, { enter, leave }, state) {
|
| 2 | visit(ast, null, enter, leave, state)
|
| 3 | }
|
| 4 |
|
| 5 | function visit(node, parent, enter, leave, state) {
|
| 6 | if (!node) return
|
| 7 |
|
| 8 | if (enter) {
|
| 9 | if (enter.some(fn => fn(node, parent, state))) return
|
| 10 | }
|
| 11 |
|
| 12 | if (Array.isArray(node.children)) {
|
| 13 | node.children.forEach(child => {
|
| 14 | child.parent = node
|
| 15 | visit(child, node, enter, leave, state)
|
| 16 | })
|
| 17 | }
|
| 18 |
|
| 19 | if (leave) {
|
| 20 | leave.forEach(fn => fn(node, parent, state))
|
| 21 | }
|
| 22 | }
|