Today I Learned - Rocky Kev

TIL Lexical Scoping

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TAGS: javascript closure

Lexical scoping is a part of Closures.

Lexical scoping describes how a parser resolves variable names when functions are nested. Lexical refers to the fact that lexical scoping uses the location where a variable is declared within the source code to determine where that variable is available. Nested functions have access to variables declared in their outer scope.

function initialize() {

  var name = 'Mozilla'; // name is a local variable created by initialize

  function displayName() { // displayName() is the inner function, a closure
    alert(name); // the variable declared in the parent function
  }

  displayName(); // will fire the displayName function

}

initialize();

This is the example in the MDN.
The variable name will stay stay and remain available for us.

Via:
MDN Web Docs: Closures

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