call-limit

call-limit
----------

Limit the number of simultaneous executions of a async function.

``javascript
const fs = require('fs')
const limit = require('call-limit')
const limitedStat = limit(fs.stat, 5)
`

Or with promise returning functions:

`javascript
const fs = Bluebird.promisifyAll(require('fs'))
const limit = require('call-limit')
const limitedStat = limit.promise(fs.statAsync, 5)
`

$3

Given that:

`javascript
const limit = require('call-limit')
`

$3

The returned function will execute up to maxRunning calls of func at once.
Beyond that they get queued and called when the previous call completes.

func must accept a callback as the final argument and must call it when
it completes, or call-limit won't know to dequeue the next thing to run.

By contrast, callers to limitedFunc do NOT have to pass in a callback, but
if they do they'll be called when func calls its callback.

$3

The returned function will execute up to maxRunning calls of func at once.
Beyond that they get queued and called when the previous call completes.

func must return a promise.

limitedFunc will return a promise that resolves with the promise returned
from the call to func.

$3

This is sugar for:

`javascript
class.prototype.methodName = limit(class.prototype.methodName, maxRunning)
`

$3

This is sugar for:

`javascript
object.methodName = limit(object.methodName, maxRunning)
`

For example limit.promise.method(fs, 'stat', 5) is the same as
fs.stat = limit.promise(fs.stat, 5).

$3

This is sugar for:

`javascript
class.prototype.methodName = limit.promise(class.prototype.methodName, maxRunning)
`

$3

This is sugar for:

`javascript
object.methodName = limit.promise(object.methodName, maxRunning)
`

For example limit.promise.method(fs, 'statAsync', 5) is the same as
fs.statAsync = limit.promise(fs.statAsync, 5)`.