What is internal scope in js

Inner scope is the creation of a local scope in JavaScript, limiting variable access to only the function or block to which it belongs, thereby encapsulating and protecting data, improving maintainability, and optimizing memory management. Creation methods include: 1. Declare variables in functions; 2. Use curly braces to define scopes in block statements.

Inner Scope

In JavaScript, an inner scope is one created within a function or block statement local scope. It gives a private scope to the declaration inside a function or block, making it inaccessible from outside.

How to create an inner scope?

In JavaScript, you can use the following methods to create internal scopes:

• Function: Variables or constants declared inside a function are only declared in that function Visible inside.
• Block statements: Block statements defined using curly braces ({}), such as if, while, or for loops, can create internal scopes.

Purposes of inner scope

Inner scope has the following purposes:

• Encapsulation : It limits variables and constants to the scope of a function or block to prevent naming conflicts between global variables and local variables.
• Data Hiding: It helps hide implementation details and make the code more modular and maintainable.
• Memory Management: When the function or block execution is completed, the variables in the inner scope will be destroyed, thereby releasing the memory.

Example

The following example demonstrates inner scope:

<code class="javascript">function outerFunction() {
  var outerVariable = "Outer Variable";

  function innerFunction() {
    var innerVariable = "Inner Variable";
    console.log(outerVariable); // "Outer Variable"
    console.log(innerVariable); // "Inner Variable"
  }

  innerFunction();
}

outerFunction();</code>

In this example, outerFunction creates creates an inner scope, and innerFunction creates another inner scope. outerVariable is visible in both scopes, while innerVariable is only visible in innerFunction.

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