expire-array

expire-array

An array-like structure that removes each element after a given timeout. Or think of it as a rolling window on top of an array which only contains the most recent elements.

Installation

npm install expire-array

Example Usage

// Initialize with a timeout of 10 seconds
var arr = require('expire-array')(1000 * 10)

// Add elements to the array using .push()
arr.push(1)

// Retrive all elements from the array using .all()
arr.all() // => [1]

setTimeout(function () {
  // after 5 seconds
  arr.push(2)
  console.log(arr.all()) // outputs: [1, 2]
}, 1000 * 5)

setTimeout(function () {
  // after 11 seconds
  console.log(arr.all()) // outputs: [2]
}, 1000 * 11)

setTimeout(function () {
  // after 16 seconds
  console.log(arr.all()) // outputs: []
}, 1000 * 16)

API

Constructor

Initialize expire-array with a timeout in milliseconds:

var ExpireArray = require('expire-array')

var arr = ExpireArray(1000 * 60) // one minute

arr.push(elm)

Add an element to the end of the array.

arr.pop()

Removes the last element from an array and returns that element.

arr.shift()

Removes the first element from an array and returns that element.

arr.all()

Returns all the elements in the array that have not expired. The returned array is a clone and none of its elements will ever expire.

arr.forEach(callback[, thisArg]) (wrapper method)

Just like the equivalent Array.prototype.forEach() method, this forEach() method executes a provided function once per array element.

Parameters

• callback - Function that produces an element of the new Array, taking two arguments
• thisArg - Optional. Value to use as this when executing callback

Callback arguments:

• currentValue - The current element being processed in the array
• index - The index of the current element being processed in the array

arr.map(callback[, thisArg]) (wrapper method)

Just like the equivalent Array.prototype.map() method, this map() method creates a new array with the results of calling a provided function on every element in this array.

Parameters

• callback - Function that produces an element of the new Array, taking two arguments
• thisArg - Optional. Value to use as this when executing callback

Callback arguments:

• currentValue - The current element being processed in the array
• index - The index of the current element being processed in the array

arr.every(callback[, thisArg]) (wrapper method)

Just like the equivalent Array.prototype.every() method, this every() method tests whether all elements in the array pass the test implemented by the provided function.

Parameters

• callback - Function to test for each element, taking two arguments
• thisArg - Optional. Value to use as this when executing callback

Callback arguments:

• currentValue - The current element being processed in the array
• index - The index of the current element being processed in the array

arr.some(callback[, thisArg]) (wrapper method)

Just like the equivalent Array.prototype.some() method, this some() method tests whether some element in the array passes the test implemented by the provided function.

Parameters

• callback - Function to test for each element, taking two arguments
• thisArg - Optional. Value to use as this when executing callback

Callback arguments:

• currentValue - The current element being processed in the array
• index - The index of the current element being processed in the array

License

MIT