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  1. Tecnología web para desarrolladores
  2. JavaScript
  3. Referencia de JavaScript
  4. Expresiones y operadores
  5. Decremento(--)
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Decremento(--)

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since julio de 2015.

El operador de decremento (--) disminuye (o resta de a uno) su operando y retorna un valor.

In this article

Pruébalo

let x = 3; const y = x--; console.log(`x:${x}, y:${y}`); // Expected output: "x:2, y:3" let a = 3; const b = --a; console.log(`a:${a}, b:${b}`); // Expected output: "a:2, b:2"

Sintaxis

Operadores: x-- o --x

Descripción

Si usamos la forma de sufijo, operador después del operando (por ejemplo, x--), el operador de disminución disminuye y devuelve el valor antes de disminuir.

Si se usamos la forma de prefijo, operador antes del operando (por ejemplo, --x), el operador de disminución disminuye y devuelve el valor después de disminuir.

Ejemplos

Usando Sufijo

js
let x = 3; y = x--; // y = 3 // x = 2

Usando Prefijo

js
let a = 2; b = --a; // a = 1 // b = 1

Especificaciones

Specification
ECMAScript® 2027 Language Specification
# sec-postfix-decrement-operator

Compatibilidad con navegadores

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  1. JavaScript
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  14. Misc
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    2. Execution model
    3. Lexical grammar
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