Provides heavy-weight extensions to the Q API for using
asynchronous promises, both in the browser and in CommonJS
module systems like NodeJS.


The Q utility module exports all of the Q module's API but
additionally provides the following functions.

    var Q = require("qq");


step(...functions)

    Calls each step function serially, proceeding only when
    the promise returned by the previous step is deeply
    resolved (see: `deep`), and passes the resolution of the
    previous step into the argument or arguments of the
    subsequent step.

    If a step accepts more than one argument, the resolution
    of the previous step is treated as an array and expanded
    into the step's respective arguments.

    `step` returns a promise for the value eventually
    returned by the last step.


delay(timeout, eventually_opt)

    Returns a promise for the eventual value after `timeout`
    miliseconds have elapsed.  `eventually` may be omitted,
    in which case the promise will be resolved to
    `undefined`.  If `eventually` is a function, progress
    will be made by calling that function and resolving to
    the returned value.  Otherwise, `eventually` is treated
    as a literal value and resolves the returned promise
    directly.


shallow(object)

    Takes any value and returns a promise for the
    corresponding value after all of its properties have
    been resolved.  For arrays, this means that the
    resolution is a new array with the corresponding values
    for each respective promise of the original array, and
    for objects, a new object with the corresponding values
    for each property.


deep(object)

    Takes any value and returns a promise for the
    corresponding value after all of its properties have
    been deeply resolved.  Any array or object in the
    transitive properties of the given value will be
    replaced with a new array or object where all of the
    owned properties have been replaced with their
    resolution.


reduceLeft(values, callback, basis, this)
reduceRight(values, callback, basis, this)
reduce(values, callback, basis, this)

    The reduce methods all have the signature of `reduce` on
    an ECMAScript 5 `Array`, but handle the cases where a
    value is a promise and when the return value of the
    accumulator is a promise.  In these cases, each reducer
    guarantees that progress will be made in a particular
    order.

    `reduceLeft` guarantees that the callback will be called
    on each value and accumulation from left to right after
    all previous values and accumulations are fully
    resolved.

    `reduceRight` works similarly from right to left.

    `reduce` is opportunistic and will attempt to accumulate
    the resolution of any previous resolutions.  This is
    useful when the accumulation function is associative.


The `qq` module provides a `Queue` object where
infinite promises for values can be dequeued before they are
enqueued.

put(value)

    Places a value on the queue, resolving the next gotten
    promise in order.

get()

    Returns a promise for the next value from the queue.  If
    more values have been enqueued than dequeued, this value
    will already be resolved.

close(reason_opt)

    Causes all promises dequeued after all already enqueued
    values have been depleted will be rejected for the given
    reason.

closed

    A promise that, when resolved, indicates that all
    enqueued values from before the call to `close` have
    been dequeued.


Copyright 2009-2011 Kristopher Michael Kowal
MIT License (enclosed)