This page is not yet available in Spanish. We are working on its translation.
If you have any questions or feedback about our current translation project,
feel free to reach out to us!
TRY THIS RULE ID: typescript-best-practices/no-explicit-any
Language: TypeScript
Severity: Notice
Category: Best Practices
Description Do not use the any
type, as it is too broad and can lead to unexpected behavior.
Non-Compliant Code Examples const number : any = 1
function generic () : any {}
function generic () : Array < any > {}
function generic () : any [] {}
function generic ( param : Array < any >) : number {}
function generic ( param : any []) : number {}
function generic ( param : Array < any >) : Array < any > {}
function generic () : Array < Array < any > > {}
function generic () : Array < any [] > {}
class Greeter { constructor ( param : Array < any >) {} }
class Greeter { message : any ; }
class Greeter { message : Array < any >; }
class Greeter { message : any []; }
class Greeter { message : Array < Array < any > > ; }
class Greeter { message : Array < any [] >; }
interface Greeter { message : any ; }
interface Greeter { message : Array < any >; }
interface Greeter { message : any []; }
interface Greeter { message : Array < Array < any > > ; }
interface Greeter { message : Array < any [] >; }
type obj = { message : any ; }
type obj = { message : Array < any >; }
type obj = { message : any []; }
type obj = { message : Array < Array < any > > ; }
type obj = { message : Array < any [] >; }
type obj = { message : string | any ; }
type obj = { message : string | Array < any >; }
type obj = { message : string | any []; }
type obj = { message : string | Array < Array < any > > ; }
type obj = { message : string | Array < any [] >; }
type obj = { message : string & any ; }
type obj = { message : string & Array < any >; }
type obj = { message : string & any []; }
type obj = { message : string & Array < Array < any > > ; }
type obj = { message : string & Array < any [] >; }
class Foo < t = any > extends Bar < any > {}
abstract class Foo < t = any > extends Bar < any > {}
abstract class Foo < t = any > implements Bar < any >, Baz < any > {}
new Foo < any >()
Foo < any >()
// https://github.com/typescript-eslint/typescript-eslint/issues/64
function test < T extends Partial < any > > () {}
const test = < T extends Partial < any > > () => {};
function foo ( a : number , ... rest : any []) : void { return ; }
type Any = any ;
function foo5 (... args : any ) {}
const bar5 = function (... args : any ) {}
const baz5 = (... args : any ) => {}
interface Qux5 { (... args : any ) : void ; }
function quux5 ( fn : (... args : any ) => void ) : void {}
function quuz5 () : ((... args : any ) => void ) {}
type Fred5 = (... args : any ) => void ;
type Corge5 = new (... args : any ) => void ;
interface Grault5 { new (... args : any ) : void ; }
interface Garply5 { f (... args : any ) : void ; }
declare function waldo5 (... args : any ) : void ;
Compliant Code Examples const number : number = 1 ;
function greet () : string {}
function greet () : Array < string > {}
function greet () : string [] {}
function greet () : Array < Array < string > > {}
function greet () : Array < string [] > {}
function greet ( param : Array < string >) : Array < string > {}
class Greeter { message : string ; }
class Greeter { message : Array < string >; }
class Greeter { message : string []; }
class Greeter { message : Array < Array < string > > ; }
class Greeter { message : Array < string [] >; }
interface Greeter { message : string ; }
interface Greeter { message : Array < string >; }
interface Greeter { message : string []; }
interface Greeter { message : Array < Array < string > > ; }
interface Greeter { message : Array < string [] >; }
type obj = { message : string ; };
type obj = { message : Array < string >; };
type obj = { message : string []; };
type obj = { message : Array < Array < string > > ; };
type obj = { message : Array < string [] >; };
type obj = { message : string | number };
type obj = { message : string | Array < string >; };
type obj = { message : string | string []; };
type obj = { message : string | Array < Array < string > > ; };
type obj = { message : string & number ; };
type obj = { message : string & Array < string >; };
type obj = { message : string & string []; };
type obj = { message : string & Array < Array < string > > ; };
// rest params enforces due to no options
// https://github.com/eslint/typescript-eslint-parser/issues/397
// function foo(a: number, ...rest: any[]): void { return; }
// function foo1(...args: any[]) {}
// const bar1 = function (...args: any[]) {};
// const baz1 = (...args: any[]) => {};
// function foo2(...args: readonly any[]) {}
// const bar2 = function (...args: readonly any[]) {};
// const baz2 = (...args: readonly any[]) => {};
// function foo3(...args: Array<any>) {}
// const bar3 = function (...args: Array<any>) {};
// const baz3 = (...args: Array<any>) => {};
// function foo4(...args: ReadonlyArray<any>) {}
// const bar4 = function (...args: ReadonlyArray<any>) {};
// const baz4 = (...args: ReadonlyArray<any>) => {};
// interface Qux1 { (...args: any[]): void; }
// interface Qux2 { (...args: readonly any[]): void; }
// interface Qux3 { (...args: Array<any>): void; }
// interface Qux4 { (...args: ReadonlyArray<any>): void; }
// function quux1(fn: (...args: any[]) => void): void {}
// function quux2(fn: (...args: readonly any[]) => void): void {}
// function quux3(fn: (...args: Array<any>) => void): void {}
// function quux4(fn: (...args: ReadonlyArray<any>) => void): void {}
// function quuz1(): (...args: any[]) => void {}
// function quuz2(): (...args: readonly any[]) => void {}
// function quuz3(): (...args: Array<any>) => void {}
// function quuz4(): (...args: ReadonlyArray<any>) => void {}
// type Fred1 = (...args: any[]) => void;
// type Fred2 = (...args: readonly any[]) => void;
// type Fred3 = (...args: Array<any>) => void;
// type Fred4 = (...args: ReadonlyArray<any>) => void;
// type Corge1 = new (...args: any[]) => void;
// type Corge2 = new (...args: readonly any[]) => void;
// type Corge3 = new (...args: Array<any>) => void;
// type Corge4 = new (...args: ReadonlyArray<any>) => void;
// interface Grault1 { new (...args: any[]): void; }
// interface Grault2 { new (...args: readonly any[]): void; }
// interface Grault3 { new (...args: Array<any>): void; }
// interface Grault4 { new (...args: ReadonlyArray<any>): void; }
// interface Garply1 { f(...args: any[]): void; }
// interface Garply2 { f(...args: readonly any[]): void; }
// interface Garply3 { f(...args: Array<any>): void; }
// interface Garply4 { f(...args: ReadonlyArray<any>): void; }
// declare function waldo1(...args: any[]): void;
// declare function waldo2(...args: readonly any[]): void;
// declare function waldo3(...args: Array<any>): void;
// declare function waldo4(...args: ReadonlyArray<any>): void;
Seamless integrations. Try Datadog Code Analysis