Package Exports
- @textlint/ast-traverse
- @textlint/ast-traverse/lib/src/index.js
This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (@textlint/ast-traverse) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.
Readme
@textlint/ast-traverse
@textlint/ast-traverse provide traversal functions for TxtAST.
This traverse function is a fork of estraverse for @textlint/markdown-to-ast.
This library is a part of textlint/textlint.
Installation
npm install @textlint/ast-traverseUsage
var parse = require("@textlint/markdown-to-ast").parse,
Syntax = require("@textlint/markdown-to-ast").Syntax;
var traverse = require("@textlint/ast-traverse").traverse,
VisitorOption = require("@textlint/ast-traverse").VisitorOption;
var AST = parse("# Header\nHello*world*");
traverse(AST, {
enter(node) {
console.log("enter", node.type);
if (node.type === Syntax.Strong) {
return VisitorOption.Skip;
}
},
leave(node) {
console.log("leave", node.type);
}
});Traversal rule is the same with Estraverse.
Example
Markdown:
Hello *world*AST:
{
"start_line": 1,
"start_column": 1,
"end_line": 0,
"children": [
{
"start_line": 1,
"start_column": 1,
"end_line": 0,
"inline_content": [
{
"c": "Hello",
"raw": "Hello",
"loc": {
"start": {
"line": 1,
"column": 0
},
"end": {
"line": 1,
"column": 5
}
},
"range": [
0,
5
],
"type": "Str"
},
{
"c": " ",
"raw": " ",
"loc": {
"start": {
"line": 1,
"column": 5
},
"end": {
"line": 1,
"column": 6
}
},
"range": [
5,
6
],
"type": "Str"
},
{
"c": [
{
"c": "world",
"raw": "world",
"loc": {
"start": {
"line": 1,
"column": 0
},
"end": {
"line": 1,
"column": 5
}
},
"range": [
0,
5
],
"type": "Str"
}
],
"raw": "*world*",
"loc": {
"start": {
"line": 1,
"column": 6
},
"end": {
"line": 1,
"column": 13
}
},
"range": [
6,
13
],
"type": "Emphasis"
}
],
"children": [],
"raw": "Hello *world*",
"loc": {
"start": {
"line": 1,
"column": 0
},
"end": {
"line": 1,
"column": 13
}
},
"range": [
0,
13
],
"type": "Paragraph"
}
],
"raw": "Hello *world*",
"loc": {
"start": {
"line": 1,
"column": 0
},
"end": {
"line": 1,
"column": 13
}
},
"range": [
0,
13
],
"type": "Document"
}Traversal all from Root(Document node):
[enter, Syntax.Document],
// # Header
[enter, Syntax.Header],
[enter, Syntax.Str],
[leave, Syntax.Str],
[leave, Syntax.Header],
// => Paragraph
[enter, Syntax.Paragraph],
[enter, Syntax.Str],
[leave, Syntax.Str],
// *world*
[enter, Syntax.Emphasis],
[enter, Syntax.Str],
[leave, Syntax.Str],
[leave, Syntax.Emphasis],
// <= Paragraph
[leave, Syntax.Paragraph],
// End
[leave, Syntax.Document]NOTE
You want to set property on Node.
Bad example:
var TraverseController = require("@textlint/ast-traverse").Controller;
var controller = new TraverseController();
controller.traverse(ast, {
enter: function (node, parent) {
node.parent = parent;// it cause a circular reference!
// do something
something(node);
}
});node.parent = parent; cause a circular reference!
Correct example:
var TraverseController = require("@textlint/ast-traverse").Controller;
var controller = new TraverseController();
controller.traverse(ast, {
enter: function (node, parent) {
// set property as non-enumerable value
Object.defineProperty(node, "parent", {
value: parent
});
// do something
something(node);
}
});Contributing
- Fork it!
- Create your feature branch:
git checkout -b my-new-feature - Commit your changes:
git commit -am 'Add some feature' - Push to the branch:
git push origin my-new-feature - Submit a pull request :D
License
MIT
and
Includes Estraverse
Copyright (C) 2012-2013 Yusuke Suzuki
https://github.com/estools/estraverse/blob/master/LICENSE.BSD