ts-simple-ast
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TypeScript compiler wrapper for AST navigation and code generation.
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---
title: Export
---
## Export
Certain nodes in TypeScript can be [exported](https://www.typescriptlang.org/docs/handbook/modules.html).
### Is export
Use `isExported()`, `isNamedExport()`, or `isDefaultExport()` methods:
```ts
functionDeclaration.isExported(); // returns: boolean
functionDeclaration.isNamedExport(); // returns: boolean
functionDeclaration.isDefaultExport(); // returns: boolean
```
### `export` and `default` keyword
Use the `has` methods to check for the `export` and `default` keywords:
```ts
functionDeclaration.hasExportKeyword(); // returns: boolean
functionDeclaration.hasDefaultKeyword(); // returns: boolean
```
And use the `get` methods to get the keywords:
```ts
functionDeclaration.getExportKeyword();
functionDeclaration.getDefaultKeyword();
```
### Setting as default export
Use `setIsDefaultExport` to set a node as being a default export or not:
```ts
functionDeclaration.setIsDefaultExport(true); // be one
functionDeclaration.setIsDefaultExport(false); // don't be one
```
Note: This will throw an exception if the node's parent is not a source file.
### Setting as export
Use `setIsExported` to set a node as being a named export if the parent is a source file or an export of a namespace if the parent is a namespace:
```ts
functionDeclaration.setIsExported(true); // be one
functionDeclaration.setIsExported(false); // don't be one
```
## Export Declarations
Export declarations look like this:
```ts
export * from "./some-file";
export {MyClass} from "./other-file";
export {MyClass};
```
Get the export declarations by calling:
```ts
const exports = sourceFile.getExportDeclarations();
// or to get the first one that matches a condition
const exportDeclaration = sourceFile.getExportDeclaration(d => d.hasNamedExports());
// tell if it has named exports
exportDeclaration.hasNamedExports();
// or if it's a namespace export
exportDeclaration.isNamespaceExport();
// get/set the module specifier
exportDeclaration.getModuleSpecifier(); // returns: string | undefined
exportDeclaration.setModuleSpecifier("./new-file");
exportDeclaration.hasModuleSpecifier(); // returns: boolean
exportDeclaration.getModuleSpecifierSourceFile(); // returns: SourceFile | undefined
```
### Add/Insert
Add or insert use `insertExportDeclaration`, `insertExportDeclarations`, `addExportDeclaration`, or `addExportDeclarations`:
```ts
const exportDeclaration = sourceFile.addExportDeclaration({
defaultImport: "MyClass",
moduleSpecifier: "./file"
});
```
### Remove
Call `.remove()`:
```ts
exportDeclaration.remove();
```
### To Namespace Export
Given an export declaration with named exports:
```ts
export {Export1, Export2, Export3} from "./other-file";
```
Calling `exportDeclaration.toNamespaceExport();` will change the code to the following:
```ts
export * from "./other-file";
```
### Named Exports
Get the named exports from an export declaration:
```ts
const namedExports = exportDeclaration.getNamedExports();
```
Adding or inserting named exports can be done via the `addNamedExport`, `addNamedExports`, `insertNamedExport`, or `insertNamedExports` methods.
```ts
const namedExport = exportDeclaration.addNamedExport({
name: "MyClass",
alias: "MyAliasName" // alias is optional
});
```
Removing one named export:
```ts
namedExport.remove();
```
#### Export specifier
Export specifiers are the individual named exports.
##### Name
```ts
namedExport.getNameNode(); // returns: Identifier
namedExport.setName("NewName");
namedExport.renameName("NewName");
```
##### Alias
```ts
namedExport.getAliasIdentifier(); // returns: Identifier | undefined
namedExport.setAlias("NewAliasName");
```
_Note:_ Setting the alias will rename any uses of the alias or identifier to the new value.
##### Local Target Declarations
The local target declarations are the declarations that the export specifier is referencing:
```ts
const declarations = namedExport.getLocalTargetDeclarations(); // returns: Node[]
```
##### Parent export declaration
```ts
namedExport.getExportDeclaration(); // returns: ExportDeclaration
```
## Export Assignments
Export assignments look like the following:
```ts
export = 5;
export default name;
```
Get the export assignments by calling:
```ts
const exportAssignments = sourceFile.getExportAssignments();
// or to get the first one that matches a condition
const exportAssignment = sourceFile.getExportAssignment(d => d.isExportEquals());
// get if it's `export =` or `export default`
const isExportEquals = exportAssignment.isExportEquals();
// get the expression
const expression = exportAssignment.getExpression();
```
### Add/Insert
Add or insert use `insertExportAssignment`, `insertExportAssignments`, `addExportAssignment`, or `addExportAssignments`:
```ts
const exportAssignment = sourceFile.addExportAssignment({
isExportEquals: true, // defaults to true
expression: "5"
});
```
### Remove
Call `.remove()`:
```ts
exportAssignment.remove();
```