package.json update with new version, required node version and descr…

…iption, also readme update

README.md

@@ -1,22 +1,30 @@
-# last-callback v 1.0.3
+# last-callback v 2.0.0
+
+Extract function's last argument and wrap with ready to invoke function.
+If last argument is callable, hence callback - wrapper will invoke it.
+Otherwise invoked wrapper do nothing.
 
 ## Description
 
-Get and call last given argument if is a function. You do not need to check last argument manually any more.
-All you need to do is to pass arguments array to this little module, then call it, or bind with `this` context.
-Last-callback always return function with built in validation. Last non callable argument will be ignored without throwing any exception.
+Last callback provides callable wrapper for last argument. There is no need for
+further checking if last argument is callable.
 
-last-callback is compatible with ES5 and latest.
+Wrapping works for infinite number of arguments even undeclared one.
 
 [![npm](https://img.shields.io/npm/l/last-callback.svg?maxAge=2592000)]()
 [![npm](https://img.shields.io/npm/dt/last-callback.svg?maxAge=2592000)]()
 [![node](https://img.shields.io/node/v/last-callback.svg?maxAge=2592000)]()
+[![CircleCI](https://img.shields.io/circleci/project/github/pawelzny/last-callback.svg)]()
 [![Maintenance](https://img.shields.io/maintenance/yes/2018.svg?maxAge=2592000)]()
 [![coverage](https://img.shields.io/badge/coverage-100%25-brightgreen.svg)]()
 
 ## Requirements
 
-NodeJS >= 4.4.0
+NodeJS >= 8.9.0
+
+<div style="color: red; font-weight: 700;">
+For NodeJS 4.4, 6.x and 7.x use last-callback version 1.0.3
+</div>
 
 ## installation
 
@@ -26,106 +34,130 @@ with NPM:
 npm install -S last-callback
 ```
 
-## Get last callback
+For older NodeJS
 
-last-callback respects: bind, call, and apply methods;
+```javascript
+npm install -S last-callback@1.0.3
+```
 
-### ES6 Style
+## Optional callback as last argument
 
-If you are using `NodeJS >= 6.2` You should definitely use __ES6 style__ with spread operators.
+**Scenario:** There is "execute" function which expect last argument to be optional callback.
 
 ```javascript
 const lastCallback = require('last-callback');
 
-function myFunc (param) {
-    let callback = lastCallback(...arguments);
+function execute(x, y, cb=null) {
+  // 'arguments' is magic variable always visible inside function.
+  let callback = lastCallback(...arguments);
+  let sum = x + y;
 
-    callback(param);
+  callback(sum);
+  return sum;
 }
 
-myFunc('test value', function (param) {
-    console.log(param); // 'test value'
-});
+execute(10, 34, (result) => console.log(result));
 ```
 
-### ES5 Style
+## Undeclared optional callback as last argument
 
-If you are still using `NodeJS < 6.2.0`, i.e. `NodeJS 4.4.7 LTS`, you can use __ES5 style__.
+**Scenario:** There is "make" function which allow callback as last argument.
 
+**TIP** Undeclared arguments will NOT be visible for debugger and IDE inspection.
 
 ```javascript
-var lastCallback = require('last-callback');
+const lastCallback = require('last-callback');
 
-function myFunc (param) {
-    var callback = lastCallback.apply(null, arguments);
+function make(x, y, z) {
+  // 'arguments' is magic variable always visible inside function.
+  let callback = lastCallback(...arguments);
+  let result = (x + y) * z;
 
-    callback(param);
+  callback(result);
+  return result;
 }
 
-myFunc('test value', function (param) {
-    console.log(param); // 'test value'
-});
+// make declared 3 arguments: 'x', 'y' and 'z'
+// but passing fourth argument is completely legal
+// and JS will not complain.
+execute(10, 34, 5, (result) => console.log(result));
 ```
 
-### ES5 Style with context
+### Calling callback with different context
+
+**Scenario:** There is 'execute' function which expect callback. There is also 'spy' object, which alter callback context.
 
 ```javascript
-var lastCallback = require('last-callback');
+const lastCallback = require('last-callback');
 
-function myFunc (param) {
-    var callback = lastCallback.apply(null, arguments);
+function returnSecret(secret) {
+  if (this.secret === undefined) {
+    this.secret = secret;
+  }
 
-    this.contextVariable = 'this is my context';
+  return this.secret;
+}
 
-    callback.call(this, param); // bind context if you need it
+// returns 'secret' without change
+function execute(secret, cb) {
+  return lastCallback(...arguments)(secret);
 }
 
-myFunc('test value', function (param) {
-    console.log(param); // 'test value'
-    console.log(this.contextVariable); // 'this is my context'
-});
+// returns 'secret' from different context
+function executeContext(secret, context, cb) {
+  return lastCallback(...arguments).call(context);
+}
+
+secretPassword = 'I am real secret';
+
+// will return 'I am real secret'
+execute(secretPassword, returnSecret);
+
+// will return 'Luke I am your father'
+executeContext(secretPassword, {secret: 'Luke I am your father}, returnSecret);
 ```
 
 ### Recursive callback
 
-You can use recursive callback if needed.
+**Scenario:** There is a 'execute' function which expected callback. The callback will be recursive.
 
 ```javascript
 const lastCallback = require('last-callback');
 
-let
-    iteration = 1,
-    limit = 5;
-
-function myFunc (iteration) {
-    let callback = lastCallback(...arguments);
-
-    callback(iteration);
+function recursiveCb (n, t) {
+  if (n < t) {
+    console.log(n)
+    recursiveCb(n + 1, t);
+  }
 }
 
-function recursiveCallabck (iteration) {
-    if (iteration >= limit) {
-        return;
-    }
-
-    console.log(iteration);
-
-    iteration += 1;
-    recursiveCallabck(iteration);
+function execute(start, stop, cb) {
+  lastCallback(...arguments)(start, stop);
 }
 
-myFunc(iteration, recursiveCallabck);
-// console log:
+execute(0, 5, recursiveCb);
+// console log result:
+// 0
 // 1
 // 2
 // 3
 // 4
-// 5
 ```
 
 ## Contribution
 
-Feel free to Pull Request
+Did you find any bugs?
+
+Maybe this documentation has language mistakes?
+
+You have idea for great new feature?
+
+
+Create new issue and describe your point of view.
+I will do my best to meet all requests.
+
+This repository is open for changes and suggestions.
+I encourage you to write your own solution and make pull request.
 
 ## LICENSE
 The MIT License (MIT)

package.json

@@ -1,13 +1,15 @@
 {
   "name": "last-callback",
-  "version": "1.0.3",
+  "version": "2.0.0",
   "author": "Paweł Zadrożny <[email protected]> (http://pawelzny.com/)",
-  "description": "Get and call last given argument if is a function.",
+  "description": "Extract function's last argument and wrap with ready to invoke function.",
   "keywords": [
     "last",
     "callback",
     "function",
-    "arguments"
+    "argument",
+    "parameter",
+    "callback wrapper"
   ],
   "license": "MIT",
   "homepage": "https://pawelzny.com/npm/last-callback",
@@ -24,7 +26,7 @@
     "coverage": "./node_modules/.bin/istanbul cover ./node_modules/.bin/_mocha"
   },
   "engines": {
-    "node": ">= 4.4.0"
+    "node": ">= 8.9.0"
   },
   "devDependencies": {
     "chai": "4.1.2",