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This project hosts practical algorithms to arrange asynchronous operations on node.js and browsers, and two specialized implementations of promises, if you need some advanced functionality.

This project provides a complete algebra over promises, and helpful utilities. Bundled deferred objects implement fast easy-to-debug promises with an extended API and functionality, including cancellable asynchronous operations, and progress signals. They are intentionally relax some Promise/A+ tenets to reduce code, and improve performance, e.g., by avoiding time-outs, which is important for client-side applications. Full interoperability with built-in ES6's Promise is provided out of box.

All algorithms (and specialized promises) can inter-operate with other implementations of promises. Everything works well with "foreign" promises as long as they are then()-able (an object or function that defines a then method).

To get more information on underlying concepts:

• Promises, deferreds, asynchronous operations.
• Differences between Promise, Deferred, and FastDeferred.

Included algorithms (work across all type of promises):

• Compositions: all(), par(), any(), one(), race().
• Generalized sequential execution of asynchronous operations: seq().
• Generalized asynchronous loop: whilst().
• The venerable when() to adapt any value to generic then()-able promises.
• Module timeout to resolve or reject promises after a timeout.

Included implementations of deferreds (can be used instead or alongside with the standard Promise):

• Module Deferred.
  • Module Deferred-ext, which adds compositions instrumented for Deferred.
• Module FastDeferred.
  • Module FastDeferred-ext, which adds compositions instrumented for FastDeferred.
• Differences between them and standard promises are described here.