# Utility functions for working with typescript's AST

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## Usage

This package consists of two major parts: utilities and typeguard functions.
By importing the project you will get both of them.
```js
import * as utils from "tsutils";
utils.isIdentifier(node); // typeguard
utils.getLineRanges(sourceFile); // utilities
```

If you don't need everything offered by this package, you can select what should be imported. The parts that are not imported are never read from disk and may save some startup time and reduce memory consumtion.

If you only need typeguards you can explicitly import them:
```js
import { isIdentifier } from "tsutils/typeguard";
// You can even distiguish between typeguards for nodes and types
import { isUnionTypeNode } from "tsutils/typeguard/node";
import { isUnionType } from "tsutils/typeguard/type";
```

If you only need the utilities you can also explicitly import them:
```js
import { forEachComment, forEachToken } from "tsutils/util";
```

### Typescript version dependency

This package is backwards compatible with typescript 2.1.0 at runtime although compiling might need a newer version of typescript installed.

Using `typescript@next` might work, but it's not officially supported. If you encounter any bugs, please open an issue.