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TypeError: "x" is not a constructor - JavaScript | MDN
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TypeError: "x" is not a constructor

    TypeError: "x" is not a constructor
    TypeError: Math is not a constructor
    TypeError: JSON is not a constructor
    TypeError: Symbol is not a constructor
    TypeError: Reflect is not a constructor
    TypeError: Intl is not a constructor
    TypeError: SIMD is not a constructor
    TypeError: Atomics is not a constructor

In this article

TypeError

?

, ( ) . constructor new operator .

String Array new, . . JavaScript : Math, JSON, Symbol, Reflect, Intl, SIMD, Atomics.

Generator functions .

js
var Car = 1;
new Car();
// TypeError: Car is not a constructor

new Math();
// TypeError: Math is not a constructor

new Symbol();
// TypeError: Symbol is not a constructor

function* f() {}
var obj = new f();
// TypeError: f is not a constructor

car

(car) . car make, model, and year . :

js
function Car(make, model, year) {
  this.make = make;
  this.model = model;
  this.year = year;
}

mycar :

js
var mycar = new Car("Eagle", "Talon TSi", 1993);

* Promise(...)* .

( ). TypeError: this is not a constructor :

js
return new Promise.resolve(true);

, Promise.resolve() Promise.reject() :

js
// This is legal, but unnecessarily long:
return new Promise((resolve, reject) => {
  resolve(true);
});

// Instead, return the static method:
return Promise.resolve(true);
return Promise.reject(false);

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  1. JavaScript
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    1. JavaScript (JS )
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    77. SyntaxError: raw bracket is not allowed in regular expression with unicode flag
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    84. SyntaxError: super() is only valid in derived class constructors
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    92. ReferenceError: deprecated caller or arguments usage
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    95. TypeError: "x" is not a constructor
    96. TypeError: "x" is not a function
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    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
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    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
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    117. TypeError: invalid 'instanceof' operand 'x'
    118. TypeError: invalid Array.prototype.sort argument
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    122. TypeError: More arguments needed
    123. TypeError: "x" has no properties
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    125. TypeError: Reduce of empty array with no initial value
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    128. TypeError: X.prototype.y called on incompatible type
    129. URIError: malformed URI sequence
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    1. JavaScript
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