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En este artículo

  • Aprende más
  1. Glossary
    1. Abstracción
    2. Accent
    3. Accesibilidad
    4. Árbol de accesibilidad (AOM)
    5. Accessible description
    6. Accessible name
    7. Adobe Flash
    8. Medida de avance
    9. AJAX
    10. Algoritmo
    11. Alignment container
    12. Alignment subject
    13. Alpha (alpha channel)
    14. ALPN
    15. API
    16. Apple Safari
    17. Contexto de aplicación
    18. Argumento
    19. ARIA
    20. ARPA
    21. Arpanet
    22. Arreglos (Matrices)
    23. ASCII
    24. Aspect ratio
    25. Asíncrono
    26. ATAG
    27. Atributo
    28. Authentication
    29. Authenticator
    30. Ancho de banda
    31. Base64 codificando y decodificando
    32. Baseline
      1. Baseline (compatibility)
      2. Baseline (typography)
    33. BCP 47 language tag
    34. Beacon
    35. Bézier curve
    36. bfcache
    37. BiDi
    38. BigInt
    39. Binding
    40. Bitwise flags
    41. Blink
    42. blink element (<blink> tag)
    43. Block
      1. Block (CSS)
      2. Block (scripting)
    44. Block cipher mode of operation
    45. Elementos en bloque
    46. Boolean
      1. Boolean (JavaScript)
      2. Boolean attribute (ARIA)
      3. Boolean attribute (HTML)
    47. Bounding Box
    48. Miga de pan
    49. Brotli compression
    50. Navegador
    51. Contexto de navegación
    52. Buffer
    53. Bun
    54. Caché
    55. Cacheable
    56. CalDAV
    57. Pila de llamadas
    58. Función Callback
    59. Camel case
    60. Canonical order
    61. Canvas
    62. Clasificación por tarjetas (card sorting)
    63. CardDAV
    64. Caret
    65. CDN
    66. Certificate authority
    67. Certified
    68. Protocolos desafío-respuesta
    69. Caracter
    70. Codificación de caracteres
    71. Character reference
    72. Conjunto de caracteres
    73. Chrome
    74. CID
    75. Algoritmo criptográfico
    76. Cipher suite
    77. Texto Cifrado
    78. Clase
    79. Client-side rendering (CSR)
    80. Clausura
    81. Cloud
    82. Cloud computing
    83. Sistema de gestión de contenidos
    84. Code point
    85. Code splitting
    86. Code unit
    87. Códec
    88. Color space
    89. Color wheel
    90. Compilar
    91. Tiempo de compilación
    92. Composite operation
    93. Compression Dictionary Transport
    94. Programación de computadoras
    95. Conditional
    96. Constante
    97. Constructor
    98. Content header
    99. Continuous Media
    100. Control flow
    101. Cookie
    102. Copyleft
    103. CORS
    104. Encabezado de solicitud incluido en la lista segura de CORS
    105. CORS-safelisted response header
    106. Crawler
    107. Credential
    108. CRLF
    109. Cross Axis
    110. CSRF
    111. Cross-site scripting
    112. CRUD
    113. Criptoanálisis
    114. Criptografía
    115. CSP
    116. CSS
    117. CSS Object Model (CSSOM)
    118. CSS pixel
    119. Preprocesador CSS
    120. Cumulative Layout Shift (CLS)
    121. Estructura de datos
    122. Database
    123. Debounce
    124. Descifrado
    125. Deep copy
    126. Delta
    127. Denial of Service (DoS)
    128. Deno
    129. Descriptor (CSS)
    130. Deserialization
    131. Developer Tools
    132. Device pixel
    133. Digital certificate
    134. Digital signature
    135. Distributed Denial of Service (DDoS)
    136. DMZ
    137. DNS
    138. Doctype
    139. Document directive
    140. Document environment
    141. DOM
    142. Dominio
    143. Nombre de dominio
    144. Domain sharding
    145. Dominator
    146. DSL
      1. DSL (Digital Subscriber Line)
      2. DSL (Domain-Specific Language)
    147. DTLS (Datagram Transport Layer Security)
    148. DTMF (Dual-Tone Multi-Frequency signaling)
    149. Tipado Dinámico
    150. ECMA
    151. ECMAScript
    152. Effective connection type
    153. Elemento
    154. Encapsulación
    155. Encriptación
    156. Endianness
    157. Engine
      1. JavaScript engine
      2. Rendering engine
    158. Entidad
    159. Entity header
    160. Enumerated
    161. Escape character
    162. eTLD
    163. Evento
    164. Exception
    165. EXIF
    166. Expando
    167. Fallback alignment
    168. Falsy
    169. Favicon
    170. Federated identity
    171. Fetch directive
    172. Fetch metadata request header
    173. Fingerprinting
    174. Firefox OS
    175. Firewall
    176. First Contentful Paint (FCP)
    177. First CPU idle
    178. First Input Delay (FID) Obsoleto
    179. First Meaningful Paint (FMP)
    180. First Paint (FP)
    181. Funcion de primera clase
    182. Flex
    183. Flex Container
    184. Flex Item
    185. Flexbox
    186. Flow relative values
    187. Nombre de encabezado prohibido
    188. Forbidden response header name
    189. Fork
    190. Fragmentainer
    191. frame rate (FPS)
    192. FTP
    193. FTU
    194. Función
    195. Fuzz testing
    196. Gamut
    197. Garbage collection
    198. Gecko
    199. Cabecera general
    200. GIF
    201. Git
    202. Global object
    203. Global scope
    204. Global variable
    205. Glyph
    206. Google Chrome
    207. GPL
    208. GPU
    209. Graceful degradation
    210. Grid
    211. Grid Areas
    212. Grid Axis
    213. Grid Cell
    214. Grid Column
    215. Grid container
    216. Líneas de Cuadrícula
    217. Grid Row
    218. Grid Tracks
    219. Guaranteed-invalid value
    220. Gutters
    221. gzip compression
    222. Hash function
    223. Hash routing
    224. Head
    225. Head-of-line blocking
    226. High-level programming language
    227. HMAC
    228. Hoisting
    229. Anfitrión
    230. Hotlink
    231. Houdini
    232. HPKP
    233. HSTS
    234. HTML
    235. HTML color codes
    236. HTML5
    237. HTTP
    238. HTTP Content
    239. HTTP header
    240. HTTP/2
    241. HTTP/3
    242. HTTPS
    243. HTTPS RR
    244. Hipervínculo
    245. Hipertexto
    246. IANA
    247. ICANN
    248. ICE
    249. IDE
    250. Idempotent
    251. Identificador
    252. Identity provider (IdP)
    253. IDL
    254. IETF
    255. IIFE: Expresión de función ejecutada inmediatamente
    256. IMAP
    257. Inmutable
    258. IndexedDB
    259. Arquitectura de la información
    260. Inheritance
    261. Ink overflow
    262. Inline-level content
    263. Input method editor
    264. Inset properties
    265. Instance
    266. Interaction to Next Paint (INP)
    267. Internationalization (i18n)
    268. Internet
    269. Interpolation
    270. Intrinsic size
    271. Invariant
    272. Dirección IP
    273. IPv4
    274. IPv6
    275. IRC
    276. ISO
    277. ISP
    278. ITU
    279. Jank
    280. Java
    281. JavaScript
    282. Jitter
    283. JPEG
    284. JSON
    285. JSON type representation
    286. Just-In-Time Compilation (JIT)
    287. Kebab case
    288. Clave
    289. Palabra clave
    290. Largest Contentful Paint (LCP)
    291. Latency
    292. Layout mode
    293. Layout viewport
    294. Lazy load
    295. Leading
    296. LGPL
    297. Ligature
    298. Literal
    299. Local scope
    300. Local variable
    301. Locale
    302. Localization
    303. Logical properties
    304. Long task
    305. Loop
    306. Lossless compression
    307. Lossy compression
    308. LTR (Left To Right)
    309. Main Axis
    310. Hilo principal
    311. Markup
    312. MathML
    313. Media
      1. Media (Audio-visual presentation)
      2. Media (CSS)
    314. Media query
    315. Metadatos
    316. Método
    317. Microsoft Edge
    318. Microsoft Internet Explorer
    319. Middleware
    320. MIME
    321. MIME type
    322. Minification
    323. MitM
    324. Mixin
    325. Mobile First
    326. Modem
    327. Modularity
    328. Mozilla Firefox
    329. Mutable
    330. MVC
    331. Espacio de Nombres
    332. NaN
    333. NAT
    334. Native
    335. Navigation directive
    336. Netscape Navigator
    337. Network throttling
    338. NNTP
    339. Node
      1. Node (DOM)
      2. Node (networking)
    340. Node.js
    341. Non-normative
    342. Normative
    343. Null
    344. Nullish value
    345. Number
    346. Object
    347. Object reference
    348. Programación orientada a objetos
    349. OpenGL
    350. OpenSSL
    351. Opera Browser
    352. Operando
    353. Operador
    354. Origin
    355. OTA
    356. OWASP
    357. P2P
    358. PAC
    359. Packet
    360. Page load time
    361. Page prediction
    362. Parameter
    363. Parent object
    364. Parse (análisis sintáctico)
    365. Parser
    366. Payload body
    367. Payload header
    368. PDF
    369. Perceived performance
    370. Percent-encoding
    371. PHP
    372. Physical properties
    373. Pixel
    374. Placeholder names
    375. Texto Simple
    376. Plugin
    377. PNG
    378. Polyfill
    379. Polymorphism
    380. POP3
    381. Puerto
    382. Prefetch
    383. Preflight petición
    384. Prerender
    385. Presto
    386. Primitivo
    387. Privileged
    388. Privileged code
    389. Mejora Progresiva
    390. Progressive web apps
    391. Promesa
    392. Propiedad
      1. Property (CSS)
      2. Property (JavaScript)
    393. Protocolo
    394. Prototipo
    395. Prototype-based programming
    396. Proxy server
    397. Pseudo-clase
    398. Pseudo-element
    399. Pseudocódigo
    400. Criptografía de clave pública
    401. Python
    402. Quality values
    403. Quaternion
    404. QUIC
    405. RAIL
    406. Random Number Generator
    407. Raster image
    408. Rate limit
    409. RDF
    410. Reading order
    411. Real User Monitoring (RUM)
    412. Recursión
    413. Reflow
    414. Expresiones regulares
    415. Relying party
    416. Render-blocking
    417. Repaint
    418. Replaced elements
    419. Replay attack
    420. Repo
    421. Reporting directive
    422. Representation header
    423. Request header
    424. Resource Timing
    425. Cabecera de respuesta
    426. Diseño web responsivo
    427. REST
    428. RGB
    429. RIL
    430. Robots.txt
    431. Round Trip Time (RTT)
    432. Router
    433. RSS
    434. Rsync
    435. RTCP (RTP Control Protocol)
    436. RTF
    437. RTL (Right to Left)
    438. RTP (Real-time Transport Protocol) and SRTP (Secure RTP)
    439. RTSP: Real-time streaming protocol
    440. Ruby
    441. Seguro
      1. Safe (HTTP Methods)
    442. Salt
    443. Same-origin policy
    444. SCV
    445. Scope
    446. Screen reader
    447. Script-supporting element
    448. Scroll boundary
    449. Scroll chaining
    450. Scroll container
    451. Scroll snap
    452. SCTP
    453. SDK (Software Development Kit)
    454. SDP
    455. Search engine
    456. Secure Context
    457. Secure Sockets Layer (SSL)
    458. Selector (CSS)
    459. Semantics
    460. SEO
    461. Serializable object
    462. Serialization
    463. Server
    464. Server Timing
    465. Server-side rendering (SSR)
    466. Session Hijacking
    467. SGML
    468. Shadow tree
    469. Shallow copy
    470. Shim
    471. Signature
      1. Signature (functions)
      2. Signature (security)
    472. SIMD
    473. SISD
    474. Site
    475. Site map
    476. SLD
    477. Modo poco riguroso — Sloppy
    478. Slug
    479. Smoke Test
    480. SMPTE (Society of Motion Picture and Television Engineers)
    481. SMTP
    482. Snake case
    483. Snap positions
    484. SOAP
    485. Source map
    486. SPA (Single-page application)
    487. Specification
    488. Optimizar sus páginas para análisis especulativo
    489. Speed index
    490. SQL
    491. SQL Injection
    492. SRI
    493. Stacking context
    494. State machine
    495. Sentencias
    496. Static method
    497. Static site generator (SSG)
    498. Tipificación estática
    499. Sticky activation
    500. Strict mode
    501. String
    502. Stringifier
    503. STUN
    504. Style origin
    505. Stylesheet
    506. Submit button
    507. SVG
    508. SVN
    509. Symbol
    510. Criptografía de clave simétrica
    511. Sincrónico
    512. Syntax
    513. Syntax error
    514. Synthetic monitoring
    515. Table grid box
    516. Table Wrapper Box
    517. Etiqueta
    518. TCP
    519. TCP handshake
    520. TCP slow start
    521. Telnet
    522. Texel
    523. The Khronos Group
    524. Thread
    525. Three js
    526. Throttle
    527. Time to first byte
    528. Time to interactive
    529. TLD
    530. TOFU
    531. Top layer
    532. Transient activation
    533. Transport Layer Security (TLS)
    534. Tree shaking
    535. Trident
    536. Truthy
    537. TTL
    538. TURN
    539. Type
    540. Coerción
    541. Type conversion
    542. TypeScript
    543. UAAG
    544. UDP (User Datagram Protocol)
    545. IU
    546. undefined
    547. Unicode
    548. Unix time
    549. URI
    550. URL
    551. URN
    552. Usenet
    553. User agent
    554. UTF-8
    555. UTF-16
    556. UUID
    557. UX
    558. Validador
    559. Valor
    560. Variable
    561. Vendor Prefix
    562. Viewport
    563. Visual Viewport
    564. Elemento vacío
    565. VoIP
    566. W3C
    567. WAI
    568. WCAG
    569. Web performance
    570. Web server
    571. Web standards
    572. WebAssembly
    573. WebDAV
    574. WebExtensions
    575. WebGL
    576. WebIDL
    577. WebKit
    578. WebM
    579. WebP
    580. WebRTC
    581. WebSockets
    582. WebVTT
    583. WHATWG
    584. Espacio en blanco
    585. WindowProxy
    586. World Wide Web
    587. Wrapper
    588. XForm Obsoleto
    589. XHTML
    590. XInclude
    591. XLink
    592. XML
    593. XMLHttpRequest (XHR)
    594. XPath
    595. XQuery
    596. XSLT
    597. Zstandard compression
  1. JavaScript
  2. Tutorials and guides
  3. Beginner's tutorials
    1. Your first website: Adding interactivity
    2. Dynamic scripting with JavaScript
    3. JavaScript frameworks and libraries
  4. JavaScript Guide
    1. Introduction
    2. Grammar and types
    3. Control flow and error handling
    4. Loops and iteration
    5. Functions
    6. Expressions and operators
    7. Numbers and strings
    8. Representing dates & times
    9. Regular expressions
    10. Indexed collections
    11. Keyed collections
    12. Working with objects
    13. Using classes
    14. Using promises
    15. JavaScript typed arrays
    16. Iterators and generators
    17. Internationalization
    18. JavaScript modules
  5. Intermediate
    1. Advanced JavaScript objects
    2. Asynchronous JavaScript
    3. Client-side web APIs
    4. Language overview
    5. JavaScript data structures
    6. Equality comparisons and sameness
    7. Enumerability and ownership of properties
    8. Closures
  6. Advanced
    1. Inheritance and the prototype chain
    2. Meta programming
    3. Memory Management
  7. References
  8. Built-in objects
    1. AggregateError
    2. Array
    3. ArrayBuffer
    4. Funciones asíncronas
    5. AsyncGenerator
    6. AsyncGeneratorFunction
    7. AsyncIterator
    8. Atomics
    9. BigInt
    10. BigInt64Array
    11. BigUint64Array
    12. Booleano
    13. DataView
    14. Date
    15. decodeURI()
    16. decodeURIComponent
    17. encodeURI
    18. encodeURIComponent()
    19. Error
    20. escape() Obsoleto
    21. eval
    22. EvalError
    23. FinalizationRegistry
    24. Float16Array
    25. Float32Array
    26. Float64Array
    27. Function
    28. Generador
    29. GeneratorFunction
    30. globalThis
    31. Infinity
    32. Int8Array
    33. Int16Array
    34. Int32Array
    35. InternalError No estándar
    36. Intl
    37. isFinite()
    38. isNaN
    39. Iterator
    40. JSON
    41. Map
    42. Math
    43. NaN
    44. Number
    45. Object
    46. parseFloat()
    47. parseInt()
    48. Promise
    49. Proxy
    50. RangeError
    51. ReferenceError
    52. Reflect
    53. RegExp
    54. Set
    55. SharedArrayBuffer
    56. String — Cadena de caracteres
    57. Symbol
    58. SyntaxError
    59. Temporal Experimental
    60. TypedArray
    61. TypeError
    62. Uint8Array
    63. Uint8ClampedArray
    64. Uint16Array
    65. Uint32Array
    66. undefined
    67. unescape() Obsoleto
    68. URIError
    69. WeakMap
    70. WeakRef
    71. WeakSet
  9. Expressions & operators
    1. Adición (+)
    2. Asignación de adición (+=)
    3. Asignacion (=)
    4. Expresión de función asíncrona
    5. async function* expression
    6. await
    7. Bitwise AND (&)
    8. Bitwise AND assignment (&=)
    9. Bitwise NOT (~)
    10. Bitwise OR (|)
    11. Bitwise OR assignment (|=)
    12. Bitwise XOR (^)
    13. Bitwise XOR assignment (^=)
    14. expresión class
    15. Operador Coma
    16. Operador condicional (ternario)
    17. Decremento(--)
    18. Operador delete
    19. La desestructuración
    20. Division (/)
    21. Division assignment (/=)
    22. Comparación (==)
    23. Exponenciación (**)
    24. Exponentiation assignment (**=)
    25. function
    26. expresión function*
    27. Greater than (>)
    28. Greater than or equal (>=)
    29. Operador de agrupación
    30. import.meta
      1. import.meta.resolve()
    31. import()
    32. in
    33. Incremento (++)
    34. Inequality (!=)
    35. instanceof
    36. Left shift (<<)
    37. Left shift assignment (<<=)
    38. Less than (<)
    39. Less than or equal (<=)
    40. Operador lógico AND (&&)
    41. Logical AND assignment (&&=)
    42. Logical NOT (!)
    43. Operador lógico OR (||)
    44. Logical OR assignment (||=)
    45. Multiplicación (*)
    46. Multiplication assignment (*=)
    47. Operador new
    48. new.target
    49. null
    50. Nullish coalescing assignment (??=)
    51. Operador de coalescencia nula (??)
    52. Object initializer
    53. Precedencia de operadores
    54. Encadenamiento opcional
    55. Miembros
    56. Resto (%)
    57. Remainder assignment (%=)
    58. Right shift (>>)
    59. Right shift assignment (>>=)
    60. Sintaxis Spread
    61. Igualdad Estricta (===)
    62. Strict inequality (!==)
    63. Sustracción (-)
    64. Asignación de sustracción (-=)
    65. super
    66. this
    67. typeof
    68. Negación unaria (-=)
    69. Unario más (+)
    70. Unsigned right shift (>>>)
    71. Unsigned right shift assignment (>>>=)
    72. void
    73. yield
    74. yield*
  10. Statements & declarations
    1. Función async
    2. async function*
    3. block
    4. break
    5. class
    6. const
    7. continue
    8. debugger
    9. do...while
    10. empty
    11. export
    12. Expression statement
    13. for
    14. for await...of
    15. for...in
    16. for...of
    17. function
    18. function*
    19. if...else
    20. import
      1. Import attributes
    21. label
    22. let
    23. return
    24. switch
    25. throw
    26. try...catch
    27. var
    28. while
    29. with Obsoleto
  11. Functions
    1. Funciones Flecha
    2. Parámetros predeterminados
    3. get
    4. Method definitions
    5. Parámetros Rest
    6. setter
    7. El objeto arguments
      1. [Symbol.iterator]()
      2. callee Obsoleto
      3. arguments.length
  12. Classes
    1. constructor
    2. extends
    3. Private class fields
    4. Class fields
    5. static
    6. Static initialization blocks
  13. Regular expressions
    1. Backreference: \1, \2
    2. Capturing group: (...)
    3. Character class escape: \d, \D, \w, \W, \s, \S
    4. Character class: [...], [^...]
    5. Character escape: \n, \u{...}
    6. Disjunction: |
    7. Input boundary assertion: ^, $
    8. Literal character: a, b
    9. Lookahead assertion: (?=...), (?!...)
    10. Lookbehind assertion: (?<=...), (?<!...)
    11. Modifier: (?ims-ims:...)
    12. Named backreference: \k<name>
    13. Named capturing group: (?<name>...)
    14. Non-capturing group: (?:...)
    15. Quantifier: *, +, ?, {n}, {n,}, {n,m}
    16. Escapes de propiedades Unicode
    17. Wildcard: .
    18. Word boundary assertion: \b, \B
  14. Errors
    1. AggregateError: No Promise in Promise.any was resolved
    2. Error: Permission denied to access property "x"
    3. InternalError: too much recursion
    4. RangeError: argument is not a valid code point
    5. RangeError: BigInt division by zero
    6. RangeError: BigInt negative exponent
    7. RangeError: form must be one of 'NFC', 'NFD', 'NFKC', or 'NFKD'
    8. RangeError: invalid array length
    9. RangeError: invalid date
    10. RangeError: precision is out of range
    11. RangeError: radix must be an integer
    12. RangeError: repeat count must be less than infinity
    13. RangeError: repeat count must be non-negative
    14. RangeError: x can't be converted to BigInt because it isn't an integer
    15. ReferenceError: "x" is not defined
    16. ReferenceError: assignment to undeclared variable "x"
    17. ReferenceError: can't access lexical declaration 'X' before initialization
    18. ReferenceError: must call super constructor before using 'this' in derived class constructor
    19. ReferenceError: super() called twice in derived class constructor
    20. SyntaxError: 'arguments'/'eval' can't be defined or assigned to in strict mode code
    21. SyntaxError: "x" is not a legal ECMA-262 octal constant
    22. SyntaxError: "use strict" no permitida en función con parámetros complejos
    23. SyntaxError: "x" is a reserved identifier
    24. SyntaxError: \ at end of pattern
    25. SyntaxError: a declaration in the head of a for-of loop can't have an initializer
    26. SyntaxError: applying the 'delete' operator to an unqualified name is deprecated
    27. SyntaxError: arguments is not valid in fields
    28. SyntaxError: await is only valid in async functions, async generators and modules
    29. SyntaxError: await/yield expression can't be used in parameter
    30. SyntaxError: cannot use `??` unparenthesized within `||` and `&&` expressions
    31. SyntaxError: character class escape cannot be used in class range in regular expression
    32. SyntaxError: continue must be inside loop
    33. SyntaxError: duplicate capture group name in regular expression
    34. SyntaxError: duplicate formal argument x
    35. SyntaxError: for-in loop head declarations may not have initializers
    36. SyntaxError: function statement requires a name
    37. SyntaxError: functions cannot be labelled
    38. SyntaxError: getter and setter for private name #x should either be both static or non-static
    39. SyntaxError: getter functions must have no arguments
    40. SyntaxError: identifier starts immediately after numeric literal
    41. SyntaxError: illegal character
    42. SyntaxError: import declarations may only appear at top level of a module
    43. SyntaxError: incomplete quantifier in regular expression
    44. SyntaxError: invalid assignment left-hand side
    45. SyntaxError: invalid BigInt syntax
    46. SyntaxError: invalid capture group name in regular expression
    47. SyntaxError: invalid character in class in regular expression
    48. SyntaxError: invalid class set operation in regular expression
    49. SyntaxError: invalid decimal escape in regular expression
    50. SyntaxError: invalid identity escape in regular expression
    51. SyntaxError: invalid named capture reference in regular expression
    52. SyntaxError: invalid property name in regular expression
    53. SyntaxError: invalid range in character class
    54. SyntaxError: invalid regexp group
    55. SyntaxError: indicador de expresión regular no válido "x"
    56. SyntaxError: invalid unicode escape in regular expression
    57. SyntaxError: JSON.parse: bad parsing
    58. SyntaxError: label not found
    59. SyntaxError: missing : after property id
    60. SyntaxError: missing ) after argument list
    61. SyntaxError: missing ) after condition
    62. SyntaxError: missing ] after element list
    63. SyntaxError: missing } after function body
    64. SyntaxError: missing } after property list
    65. SyntaxError: missing = in const declaration
    66. SyntaxError: missing formal parameter
    67. SyntaxError: missing name after . operator
    68. SyntaxError: missing variable name
    69. SyntaxError: negated character class with strings in regular expression
    70. SyntaxError: new keyword cannot be used with an optional chain
    71. SyntaxError: nothing to repeat
    72. SyntaxError: numbers out of order in {} quantifier.
    73. SyntaxError: octal escape sequences can't be used in untagged template literals or in strict mode code
    74. SyntaxError: parameter after rest parameter
    75. SyntaxError: private fields can't be deleted
    76. SyntaxError: property name __proto__ appears more than once in object literal
    77. SyntaxError: raw bracket is not allowed in regular expression with unicode flag
    78. SyntaxError: redeclaration of formal parameter "x"
    79. SyntaxError: reference to undeclared private field or method #x
    80. SyntaxError: rest parameter may not have a default
    81. SyntaxError: return not in function
    82. SyntaxError: setter functions must have one argument
    83. SyntaxError: string literal contains an unescaped line break
    84. SyntaxError: super() is only valid in derived class constructors
    85. SyntaxError: tagged template cannot be used with optional chain
    86. SyntaxError: Unexpected '#' used outside of class body
    87. SyntaxError: Unexpected token
    88. SyntaxError: unlabeled break must be inside loop or switch
    89. SyntaxError: unparenthesized unary expression can't appear on the left-hand side of '**'
    90. SyntaxError: use of super property/member accesses only valid within methods or eval code within methods
    91. SyntaxError: Using //@ to indicate sourceURL pragmas is deprecated. Use //# instead
    92. TypeError: 'caller', 'callee', and 'arguments' properties may not be accessed
    93. TypeError: 'x' is not iterable
    94. TypeError: "x" is (not) "y"
    95. TypeError: "x" is not a constructor
    96. TypeError: "x" is not a function
    97. TypeError: "x" is not a non-null object
    98. TypeError: "x" is read-only
    99. TypeError: already executing generator
    100. TypeError: BigInt value can't be serialized in JSON
    101. TypeError: calling a builtin X constructor without new is forbidden
    102. TypeError: can't access/set private field or method: object is not the right class
    103. TypeError: can't assign to property "x" on "y": not an object
    104. TypeError: can't convert BigInt to number
    105. TypeError: can't convert x to BigInt
    106. TypeError: can't define property "x": "obj" is not extensible
    107. TypeError: can't delete non-configurable array element
    108. TypeError: can't redefine non-configurable property "x"
    109. TypeError: can't set prototype of this object
    110. TypeError: can't set prototype: it would cause a prototype chain cycle
    111. TypeError: cannot use 'in' operator to search for 'x' in 'y'
    112. TypeError: class constructors must be invoked with 'new'
    113. TypeError: cyclic object value
    114. TypeError: derived class constructor returned invalid value x
    115. TypeError: getting private setter-only property
    116. TypeError: Initializing an object twice is an error with private fields/methods
    117. TypeError: invalid 'instanceof' operand 'x'
    118. TypeError: invalid Array.prototype.sort argument
    119. TypeError: invalid assignment to const "x"
    120. TypeError: Iterator/AsyncIterator constructor can't be used directly
    121. TypeError: matchAll/replaceAll must be called with a global RegExp
    122. TypeError: More arguments needed
    123. TypeError: null/undefined has no properties
    124. TypeError: property "x" is non-configurable and can't be deleted
    125. TypeError: Reduce of empty array with no initial value
    126. TypeError: setting getter-only property "x"
    127. TypeError: WeakSet key/WeakMap value 'x' must be an object or an unregistered symbol
    128. TypeError: X.prototype.y called on incompatible type
    129. URIError: malformed URI sequence
    130. Warning: -file- is being assigned a //# sourceMappingURL, but already has one
    131. Warning: unreachable code after return statement
  15. Misc
    1. JavaScript technologies overview
    2. Execution model
    3. Lexical grammar
    4. Iteration protocols
    5. Strict mode
    6. Template literals
    7. Trailing commas
    8. Deprecated features

En este artículo

  • Aprende más

Variable

Una variable es una ubicación nombrada para almacenar un valor. De esta manera se puede acceder a un valor impredecible por medio de un nombre predeterminado.

Aprende más

Conocimientos generales

  • Variable (computer science) en Wikipedia

Referencia técnica

  • Declarar variables en JavaScript
  • Declaración var en JavaScript

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