Скачать или смотреть learn closures in 13 minutes

Download 1M+ code from https://codegive.com/3f01244
learning closures in javascript in 13 minutes

what is a closure?

a closure is a feature in javascript where an inner function has access to its outer function's variables (scope) even after the outer function has completed execution. this powerful concept allows for data encapsulation and helps in maintaining state in a functional way.

basic concept of closures

when a function is created, it forms a closure that includes the function's scope, its variables, and any other variables from the surrounding (outer) function scopes.

why use closures?

1. *data encapsulation:* closures allow you to hide variables from the global scope.
2. *partial application / currying:* you can create functions with preset parameters.
3. *maintaining state:* closures can maintain state in a functional way.

basic example of a closure

let's start with a simple example of a closure:



breakdown of the example

1. *outer function:* `outerfunction` has a variable `outervariable`.
2. *inner function:* `innerfunction` can access `outervariable` because of the closure created.
3. *returning inner function:* when we call `outerfunction`, it returns `innerfunction`, which retains access to `outervariable`.

practical use case: creating a counter

let's see a practical example of how closures can be used to create a counter:



explanation of the counter example

1. *private variable:* the `count` variable is private to the `createcounter` function.
2. *returned object:* we return an object with methods (`increment`, `decrement`, `reset`) that form closures around the `count` variable.
3. *state maintenance:* each method can access and modify `count`, maintaining its state even after `createcounter` has finished executing.

closures with settimeout

closures are also useful in asynchronous programming, as shown below:



explanation

in this example, if we used `var` instead of `let`, you would see `3` logged three times due to variable hoisting. using `let` creat ...

#LearnClosures #JavaScriptTutorial #axios
learn closures
closures in JavaScript
JavaScript closures tutorial
understanding closures
closures explained
quick guide to closures
closures for beginners
JavaScript scope
lexical scoping
function scope
closures examples
JavaScript functions
asynchronous closures
closure use cases
mastering closures