Possible Errors

Best Practices

Strict Mode

Variables

Node.js and CommonJS

Stylistic Issues

ECMAScript 6

arrow-body-style

Require braces around arrow function bodies

arrow-parens

Require parentheses around arrow function arguments

arrow-spacing

Enforce consistent spacing before and after the arrow in arrow functions

constructor-super

Require super() calls in constructors

generator-star-spacing

Enforce consistent spacing around * operators in generator functions

no-class-assign

Disallow reassigning class members

no-confusing-arrow

Disallow arrow functions where they could be confused with comparisons

no-const-assign

Disallow reassigning const variables

no-dupe-class-members

Disallow duplicate class members

no-duplicate-imports

Disallow duplicate module imports

no-new-symbol

Disallow new operators with the Symbol object

no-restricted-imports

Disallow specified modules when loaded by import

no-this-before-super

Disallow this/super before calling super() in constructors

no-useless-computed-key

Disallow unnecessary computed property keys in object literals

no-useless-constructor

Disallow unnecessary constructors

no-useless-rename

Disallow renaming import, export, and destructured assignments to the same name

no-var

Require let or const instead of var

object-shorthand

Require or disallow method and property shorthand syntax for object literals

prefer-arrow-callback

Require using arrow functions for callbacks

prefer-const

Require const declarations for variables that are never reassigned after declared

prefer-destructuring

Require destructuring from arrays and/or objects

prefer-numeric-literals

Disallow parseInt() and Number.parseInt() in favor of binary, octal, and hexadecimal literals

prefer-rest-params

Require rest parameters instead of arguments

prefer-spread

Require spread operators instead of .apply()

prefer-template

Require template literals instead of string concatenation

require-yield

Require generator functions to contain yield

rest-spread-spacing

Enforce spacing between rest and spread operators and their expressions

sort-imports

Enforce sorted import declarations within modules

symbol-description

Require symbol descriptions

template-curly-spacing

Require or disallow spacing around embedded expressions of template strings

yield-star-spacing

Require or disallow spacing around the * in yield* expressions

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prefer-const

- Require const declarations for variables that are never reassigned after declared

This rule is aimed at flagging variables that are declared using let keyword, but never reassigned after the initial assignment.

What ESLint should do when it catches the rule break

Show a warning

Options

ignoreReadBeforeAssign

Ignores variables that are read between the declaration and the first assignment.

destructuring

any

Rule examples

You can check them out here.

prefer-arrow-callback prefer-destructuring