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SyntaxError: indicador de expresión regular no válido "x"

La excepción de JavaScript "indicador de expresión regular no válido" se produce cuando las indicadores, definidas después de la segunda barra en la expresión regular literal, no son de g, i, m, s, u o y.

In this article

Mensaje

SyntaxError: error de sintaxis en la expresión regular (Edge) SyntaxError: marca de expresión regular no válida "x" (Firefox) SyntaxError: indicadores de expresión regular no válidos (Chrome)

Tipo Error

SyntaxError

¿Qué salió mal?

Hay indicadores de expresión regular no válidos en el código. En una expresión regular literal, que consiste en un patrón encerrado entre barras, los indicadores se definen después de la segunda barra. También se pueden definir en la función constructora del objeto RegExp (segundo parámetro). Los indicadores de expresión regular se pueden usar por separado o juntos en cualquier orden, pero solo hay seis de ellos en ECMAScript.

Para incluir una bandera con la expresión regular, usa esta sintaxis:

js
var re = /patrón/indicadores;

o

js
var re = new RegExp("patrón", "indicadores");
Bandera Descripción
g Búsqueda global.
i Búsqueda que no distingue entre mayúsculas y minúsculas.
m Búsqueda multilínea.
s Permite que el punto (.) coincida con las nuevas líneas (agregado en ECMAScript 2018)
u Unicode; trata el patrón como una secuencia de puntos de código Unicode
y Realiza una búsqueda "pegajosa" que coincida a partir de la posición actual en la cadena de destino. Consulta sticky

Ejemplos

Solo hay seis indicadores de expresión regular válidos.

js
/foo/bar; // SyntaxError: indicador de expresión regular no válido "b"

¿Tenías la intención de crear una expresión regular? Una expresión que contiene dos barras se interpreta como una expresión regular literal.

js
let obj = { url: /docs/Web }; // SyntaxError: indicador de expresión regular no válido "W"

¿O pretendías crear una cadena en su lugar? Agrega comillas simples o dobles para crear una cadena literal.

js
let obj = { url: "/docs/Web", };

Indicadores de expresión regular válidos

Consulta la tabla anterior para ver las seis marcas de expresiones regulares válidas que están permitidas en JavaScript.

js
/foo/g; /foo/gims; /foo/uy;

Ve también

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  1. JavaScript
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  3. JavaScript Guide
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  4. Intermediate
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    31. SyntaxError: character class escape cannot be used in class range in regular expression
    32. SyntaxError: continue must be inside loop
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    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
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    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
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    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
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    110. TypeError: can't set prototype: it would cause a prototype chain cycle
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    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
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    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
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    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
  14. 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

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