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      Web technology reference for developers

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      Structure of content on the web

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      Code used to describe document style

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      General-purpose scripting language

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      Interfaces for building web applications

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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. Advance measure
    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. Beacon
    34. Bézier curve
    35. bfcache
    36. BiDi
    37. BigInt
    38. Binding
    39. Bitwise flags
    40. Blink
    41. blink element (<blink> tag)
    42. Block
      1. Block (CSS)
      2. Block (scripting)
    43. Block cipher mode of operation
    44. Elementos en bloque
    45. Boolean
      1. Boolean (JavaScript)
      2. Boolean attribute (ARIA)
      3. Boolean attribute (HTML)
    46. Bounding Box
    47. Miga de pan
    48. Brotli compression
    49. Navegador
    50. Contexto de navegación
    51. Buffer
    52. Bun
    53. Caché
    54. Cacheable
    55. CalDAV
    56. Pila de llamadas
    57. Función Callback
    58. Camel case
    59. Canonical order
    60. Canvas
    61. Clasificación por tarjetas (card sorting)
    62. CardDAV
    63. Caret
    64. CDN
    65. Certificate authority
    66. Certified
    67. Protocolos desafío-respuesta
    68. Caracter
    69. Codificación de caracteres
    70. Character reference
    71. Conjunto de caracteres
    72. Chrome
    73. CID
    74. Algoritmo criptográfico
    75. Cipher suite
    76. Texto Cifrado
    77. Clase
    78. Client-side rendering (CSR)
    79. Clausura
    80. Cloud
    81. Cloud computing
    82. Sistema de gestión de contenidos
    83. Code point
    84. Code splitting
    85. Code unit
    86. Códec
    87. Color space
    88. Color wheel
    89. Compilar
    90. Tiempo de compilación
    91. Composite operation
    92. Compression Dictionary Transport
    93. Programación de computadoras
    94. Conditional
    95. Constante
    96. Constructor
    97. Content header
    98. Continuous Media
    99. Control flow
    100. Cookie
    101. Copyleft
    102. CORS
    103. Encabezado de solicitud incluido en la lista segura de CORS
    104. CORS-safelisted response header
    105. Crawler
    106. Credential
    107. CRLF
    108. Cross Axis
    109. Cross-site scripting
    110. CRUD
    111. Criptoanálisis
    112. Criptografía
    113. CSP
    114. CSRF
    115. CSS
    116. CSS Object Model (CSSOM)
    117. CSS pixel
    118. Preprocesador CSS
    119. Cumulative Layout Shift (CLS)
    120. Estructura de datos
    121. Database
    122. Debounce
    123. Descifrado
    124. Deep copy
    125. Delta
    126. Denial of Service (DoS)
    127. Deno
    128. Descriptor (CSS)
    129. Deserialization
    130. Developer Tools
    131. Device pixel
    132. Digital certificate
    133. Digital signature
    134. Distributed Denial of Service (DDoS)
    135. DMZ
    136. DNS
    137. Doctype
    138. Document directive
    139. Document environment
    140. DOM
    141. Dominio
    142. Nombre de dominio
    143. Domain sharding
    144. Dominator
    145. DSL
      1. DSL (Digital Subscriber Line)
      2. DSL (Domain-Specific Language)
    146. DTLS (Datagram Transport Layer Security)
    147. DTMF (Dual-Tone Multi-Frequency signaling)
    148. Tipado Dinámico
    149. ECMA
    150. ECMAScript
    151. Effective connection type
    152. Elemento
    153. Encapsulación
    154. Encriptación
    155. Endianness
    156. Engine
      1. JavaScript engine
      2. Rendering engine
    157. Entidad
    158. Entity header
    159. Enumerated
    160. Escape character
    161. eTLD
    162. Evento
    163. Exception
    164. EXIF
    165. Expando
    166. Fallback alignment
    167. Falsy
    168. Favicon
    169. Federated identity
    170. Fetch directive
    171. Fetch metadata request header
    172. Fingerprinting
    173. Firefox OS
    174. Firewall
    175. First Contentful Paint (FCP)
    176. First CPU idle
    177. First Input Delay (FID) Obsoleto
    178. First Meaningful Paint (FMP)
    179. First Paint (FP)
    180. Funcion de primera clase
    181. Flex
    182. Flex Container
    183. Flex Item
    184. Flexbox
    185. Flow relative values
    186. Nombre de encabezado prohibido
    187. Forbidden response header name
    188. Fork
    189. Fragmentainer
    190. frame rate (FPS)
    191. FTP
    192. FTU
    193. Función
    194. Fuzz testing
    195. Gamut
    196. Garbage collection
    197. Gecko
    198. Cabecera general
    199. GIF
    200. Git
    201. Global object
    202. Global scope
    203. Global variable
    204. Glyph
    205. Google Chrome
    206. GPL
    207. GPU
    208. Graceful degradation
    209. Grid
    210. Grid Areas
    211. Grid Axis
    212. Grid Cell
    213. Grid Column
    214. Grid container
    215. Líneas de Cuadrícula
    216. Grid Row
    217. Grid Tracks
    218. Guaranteed-invalid value
    219. Gutters
    220. gzip compression
    221. Hash function
    222. Head
    223. Head-of-line blocking
    224. High-level programming language
    225. HMAC
    226. Hoisting
    227. Anfitrión
    228. Hotlink
    229. Houdini
    230. HPKP
    231. HSTS
    232. HTML
    233. HTML color codes
    234. HTML5
    235. HTTP
    236. HTTP Content
    237. HTTP header
    238. HTTP/2
    239. HTTP/3
    240. HTTPS
    241. HTTPS RR
    242. Hipervínculo
    243. Hipertexto
    244. IANA
    245. ICANN
    246. ICE
    247. IDE
    248. Idempotent
    249. Identificador
    250. Identity provider (IdP)
    251. IDL
    252. IETF
    253. IIFE: Expresión de función ejecutada inmediatamente
    254. IMAP
    255. Inmutable
    256. IndexedDB
    257. Arquitectura de la información
    258. Inheritance
    259. Ink overflow
    260. Inline-level content
    261. Input method editor
    262. Inset properties
    263. Instance
    264. Interaction to Next Paint (INP)
    265. Internationalization (i18n)
    266. Internet
    267. Interpolation
    268. Intrinsic size
    269. Dirección IP
    270. IPv4
    271. IPv6
    272. IRC
    273. ISO
    274. ISP
    275. ITU
    276. Jank
    277. Java
    278. JavaScript
    279. Jitter
    280. JPEG
    281. JSON
    282. JSON type representation
    283. Just-In-Time Compilation (JIT)
    284. Kebab case
    285. Clave
    286. Palabra clave
    287. Largest Contentful Paint (LCP)
    288. Latency
    289. Layout mode
    290. Layout viewport
    291. Lazy load
    292. Leading
    293. LGPL
    294. Ligature
    295. Literal
    296. Local scope
    297. Local variable
    298. Locale
    299. Localization
    300. Logical properties
    301. Long task
    302. Loop
    303. Lossless compression
    304. Lossy compression
    305. LTR (Left To Right)
    306. Main Axis
    307. Hilo principal
    308. Markup
    309. MathML
    310. Media
      1. Media (Audio-visual presentation)
      2. Media (CSS)
    311. Media query
    312. Metadatos
    313. Método
    314. Microsoft Edge
    315. Microsoft Internet Explorer
    316. Middleware
    317. MIME
    318. MIME type
    319. Minification
    320. MitM
    321. Mixin
    322. Mobile First
    323. Modem
    324. Modularity
    325. Mozilla Firefox
    326. Mutable
    327. MVC
    328. Espacio de Nombres
    329. NaN
    330. NAT
    331. Native
    332. Navigation directive
    333. Netscape Navigator
    334. Network throttling
    335. NNTP
    336. Node
      1. Node (DOM)
      2. Node (networking)
    337. Node.js
    338. Non-normative
    339. Normative
    340. Null
    341. Nullish value
    342. Number
    343. Object
    344. Object reference
    345. Programación orientada a objetos
    346. OpenGL
    347. OpenSSL
    348. Opera Browser
    349. Operando
    350. Operador
    351. Origin
    352. OTA
    353. OWASP
    354. P2P
    355. PAC
    356. Packet
    357. Page load time
    358. Page prediction
    359. Parameter
    360. Parent object
    361. Parse (análisis sintáctico)
    362. Parser
    363. Payload body
    364. Payload header
    365. PDF
    366. Perceived performance
    367. Percent-encoding
    368. PHP
    369. Physical properties
    370. Pixel
    371. Placeholder names
    372. Texto Simple
    373. Plugin
    374. PNG
    375. Polyfill
    376. Polymorphism
    377. POP3
    378. Puerto
    379. Prefetch
    380. Preflight petición
    381. Prerender
    382. Presto
    383. Primitivo
    384. Privileged
    385. Privileged code
    386. Mejora Progresiva
    387. Progressive web apps
    388. Promesa
    389. Propiedad
      1. Property (CSS)
      2. Property (JavaScript)
    390. Protocolo
    391. Prototipo
    392. Prototype-based programming
    393. Proxy server
    394. Pseudo-clase
    395. Pseudo-element
    396. Pseudocódigo
    397. Criptografía de clave pública
    398. Python
    399. Quality values
    400. Quaternion
    401. QUIC
    402. RAIL
    403. Random Number Generator
    404. Raster image
    405. Rate limit
    406. RDF
    407. Real User Monitoring (RUM)
    408. Recursión
    409. Reflow
    410. Expresiones regulares
    411. Relying party
    412. Render-blocking
    413. Repaint
    414. Replaced elements
    415. Replay attack
    416. Repo
    417. Reporting directive
    418. Representation header
    419. Request header
    420. Resource Timing
    421. Cabecera de respuesta
    422. Diseño web responsivo
    423. REST
    424. RGB
    425. RIL
    426. Robots.txt
    427. Round Trip Time (RTT)
    428. Router
    429. RSS
    430. Rsync
    431. RTCP (RTP Control Protocol)
    432. RTF
    433. RTL (Right to Left)
    434. RTP (Real-time Transport Protocol) and SRTP (Secure RTP)
    435. RTSP: Real-time streaming protocol
    436. Ruby
    437. Seguro
      1. Safe (HTTP Methods)
    438. Salt
    439. Same-origin policy
    440. SCV
    441. Scope
    442. Screen reader
    443. Script-supporting element
    444. Scroll boundary
    445. Scroll chaining
    446. Scroll container
    447. Scroll snap
    448. SCTP
    449. SDK (Software Development Kit)
    450. SDP
    451. Search engine
    452. Secure Context
    453. Secure Sockets Layer (SSL)
    454. Selector (CSS)
    455. Semantics
    456. SEO
    457. Serializable object
    458. Serialization
    459. Server
    460. Server Timing
    461. Server-side rendering (SSR)
    462. Session Hijacking
    463. SGML
    464. Shadow tree
    465. Shallow copy
    466. Shim
    467. Signature
      1. Signature (functions)
      2. Signature (security)
    468. SIMD
    469. SISD
    470. Site
    471. Site map
    472. SLD
    473. Modo poco riguroso — Sloppy
    474. Slug
    475. Smoke Test
    476. SMPTE (Society of Motion Picture and Television Engineers)
    477. SMTP
    478. Snake case
    479. Snap positions
    480. SOAP
    481. Source map
    482. SPA (Single-page application)
    483. Specification
    484. Optimizar sus páginas para análisis especulativo
    485. Speed index
    486. SQL
    487. SQL Injection
    488. SRI
    489. Stacking context
    490. State machine
    491. Sentencias
    492. Static method
    493. Static site generator (SSG)
    494. Tipificación estática
    495. Sticky activation
    496. Strict mode
    497. String
    498. Stringifier
    499. STUN
    500. Style origin
    501. Stylesheet
    502. Submit button
    503. SVG
    504. SVN
    505. Symbol
    506. Criptografía de clave simétrica
    507. Sincrónico
    508. Syntax
    509. Syntax error
    510. Synthetic monitoring
    511. Table grid box
    512. Table Wrapper Box
    513. Etiqueta
    514. TCP
    515. TCP handshake
    516. TCP slow start
    517. Telnet
    518. Texel
    519. The Khronos Group
    520. Thread
    521. Three js
    522. Throttle
    523. Time to first byte
    524. Time to interactive
    525. TLD
    526. TOFU
    527. Top layer
    528. Transient activation
    529. Transport Layer Security (TLS)
    530. Tree shaking
    531. Trident
    532. Truthy
    533. TTL
    534. TURN
    535. Type
    536. Coerción
    537. Type conversion
    538. TypeScript
    539. UAAG
    540. UDP (User Datagram Protocol)
    541. IU
    542. undefined
    543. Unicode
    544. Unix time
    545. URI
    546. URL
    547. URN
    548. Usenet
    549. User agent
    550. UTF-8
    551. UUID
    552. UX
    553. Validador
    554. Valor
    555. Variable
    556. Vendor Prefix
    557. Viewport
    558. Visual Viewport
    559. Elemento vacío
    560. VoIP
    561. W3C
    562. WAI
    563. WCAG
    564. Web performance
    565. Web server
    566. Web standards
    567. WebAssembly
    568. WebDAV
    569. WebExtensions
    570. WebGL
    571. WebIDL
    572. WebKit
    573. WebM
    574. WebP
    575. WebRTC
    576. WebSockets
    577. WebVTT
    578. WHATWG
    579. Espacio en blanco
    580. WindowProxy
    581. World Wide Web
    582. Wrapper
    583. XForm Obsoleto
    584. XHTML
    585. XInclude
    586. XLink
    587. XML
    588. XMLHttpRequest (XHR)
    589. XPath
    590. XQuery
    591. XSLT
    592. 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. Meta programming
    19. 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. 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. Int16Array
    33. Int32Array
    34. Int8Array
    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. Uint16Array
    63. Uint32Array
    64. Uint8Array
    65. Uint8ClampedArray
    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. callee Obsoleto
      2. arguments.length
      3. arguments[Symbol.iterator]()
  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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