JavaScript code modules

JavaScript code modules let multiple privileged JavaScript scopes share code. For example, a module could be used by Firefox itself as well as by extensions, in order to avoid code duplication.

General topics

Using JavaScript code modules: An introduction to how to use JavaScript code modules.
Component.utils.import: How to import a JavaScript code module.
Component.utils.unload: How to unload a JavaScript code module.
Code snippets: Modules: Examples of how to use code modules.
Mozilla Labs JS Modules: This page features a list of JS modules, along with download links and documentation, that extension developers can use in their code.

Standard code modules

AddonManager.jsm: Interface to install, manage, and uninstall add-ons.
AddonRepository.jsm: Allows searching of the add-ons repository.
Assert.jsm: Implements the CommonJS Unit Testing specification version 1.1, which provides a basic, standardized interface for performing in-code logical assertions with optional, customizable error reporting.
ctypes.jsm: Provides an interface that allows JavaScript code to call native libraries without requiring the development of an XPCOM component.
DeferredTask.jsm: Run a task after a delay.
Dict.jsm: Provides an API for key/value pair dictionaries.
DownloadLastDir.jsm: Provides the path to the directory into which the last download occurred.
Downloads.jsm: Provides a single entry point to interact with the downloading capabilities of the platform.
FileUtils.jsm: Provides helpers for dealing with files.
Geometry.jsm: Provides routines for performing basic geometric operations on points and rectangles.
ISO8601DateUtils.jsm: Provides routines to convert between JavaScript Date objects and ISO 8601 date strings.
Log.jsm (formerly log4moz): Provides a log4j style API for logging log messages to various endpoints, such as the Browser Console or a file on disk. This module was formerly
NetUtil.jsm: Provides helpful networking utility functions, including the ability to easily copy data from an input stream to an output stream asynchronously.
openLocationLastURL.jsm: Provides access to the last URL opened using the "Open Location" option in the File menu.
osfile.jsm: Provides routines to access files. Read, write, rename, create directories, ...
PerfMeasurement.jsm: Provides access to low-level hardware and OS performance measurement tools.
PluralForm.jsm: Provides an easy way to get the correct plural forms for the current locale, as well as ways to localize to a specific plural rule.
PopupNotifications.jsm: Provides an easy way to present non-modal notifications to users.
Promise.jsm: Implements the Promises/A+ proposal as known in April 2013.
Services.jsm: Provides getters for conveniently obtaining access to commonly-used services.
source-editor.jsm: The Source Editor is used by developer tools such as the Style Editor; this interface implements the editor and lets you interact with it.
Sqlite.jsm: A Promise-based API to mozIStorage/SQLite.
Task.jsm: Implements a subset of Task.js to make sequential, asynchronous operations simple, using the power of JavaScript's yield operator.
Timer.jsm: A pure JS implementation of window.setTimeout.
XPCOMUtils.jsm: Contains utilities for JavaScript components loaded by the JS component loader.

JavaScript code modules

General topics

Standard code modules

Document Tags and Contributors

MDN Survey

JavaScript code modules

General topics

Standard code modules

Document Tags and Contributors

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