Yahoo! UI Library

Mechanism to execute a series of callbacks in a non-blocking queue. Each callback is executed via setTimout unless configured with a negative timeout, in which case it is run in blocking mode in the same execution thread as the previous callback. Callbacks can be function references or object literals with the following keys:

• fn - {Function} REQUIRED the callback function.
• timeout - {number} millisecond delay to wait after previous callback completion before executing this callback. Negative values cause immediate blocking execution. Default 0.
• until - {Function} boolean function executed before each iteration. Return true to indicate callback completion.
• iterations - {Number} number of times to execute the callback before proceeding to the next callback in the queue. Incompatible with until.