typescript-walk
Simple package for traversing typescript AST nodes.
This package version will be inferred from typescript package version.
For example typescript 2.6.1 will generate 2.6.1# where # is this package revision number - 2.6.10, 2.6.142 for example
Installation
$ npm install typescript-walk
API
visit (node: ts.Node, visitor: Visitor) => void;
Main function of this package. Requires typescript AST node and instance of Visitor object.
Visitor
Helper type describing Visitor object used for visiting AST nodes.
Example
import * as fs from 'fs';
import * as path from 'path';
import * as ts from 'typescript';
import { visit, Visitor } from './index';
// visitor class
class MyVisitor implements Visitor {
// do whatever u need ...
readonly kinds: string[];
constructor() {
this.kinds = [];
}
// default handler - called in case of undeclared handler
Default(node: ts.Node) {
this.kinds.push(ts.SyntaxKind[node.kind]);
}
// handler for ts.SyntaxKind.Block
Block(_: ts.Block) {
this.kinds.push('BLOCK');
}
// handler for ts.SyntaxKind.Expression
Expression(_: ts.Expression): false {
this.kinds.push('EXPRESSION');
// skips traversin children
return false;
}
}
// load & parse file
const fileName: string = ...
const sourceFile = ts.createSourceFile(
fileName,
fs.readFileSync(fileName, 'utf8'),
ts.ScriptTarget.Latest,
true,
);
// walk AST
const visitor = new MyVisitor();
visit(sourceFile, visitor);
// show results
console.log(visitor.kinds.join('\n'));
