Require let or const instead of var
TRY THIS RULE ID: javascript-code-style/no-var
Language: JavaScript
Severity: Notice
Category: Best Practices
Description Block scoped lexical declarations like let and const are preferred over var. Block scope is common in many other programming languages and helps programmers avoid mistakes.
Non-Compliant Code Examples var foo = bar ;
var foo = bar , toast = most ;
var foo = bar ; let toast = most ;
for ( var a of b ) { console . log ( a ); }
for ( var a in b ) { console . log ( a ); }
for ( let a of b ) { var c = 1 ; console . log ( c ); }
for ( var i = 0 ; i < list . length ; ++ i ) { foo ( i ) }
for ( var i = 0 ; i < 10 ; ++ i ) {};
for ( var a of b ) { arr . push (() => a ); }
for ( let a of b ) { var c ; console . log ( c ); c = 'hello' ; }
var a = a ;
var { a = a } = {};
var { a = b , b } = {};
let { a , b = a } = {};
var a = b , b = 1 ;
let a = b ; var b = 1 ;
function foo () { a } var a = 1 ; foo ();
if ( foo ) var bar = 1 ;
var foo = 1 ;
{ var foo = 1 }
if ( true ) { var foo = 1 }
var foo = 1 ;
declare var foo = 2 ;
function foo () { var let ; }
function foo () { var { let } = {}; }
function foo () { a }
var a = 1 ; foo ();
Compliant Code Examples const JOE = 'schmoe' ;
let moo = 'car' ;
const JOE = 'schmoe' ;
let moo = 'car' ;
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