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TypeError: can't redefine non-configurable property "x" - JavaScript | MDN
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TypeError: can't redefine non-configurable property "x"

TypeError: can't redefine non-configurable property "x" (Firefox)
TypeError: Cannot redefine property: "x" (Chrome)

TypeError

configurable (writable ) Object.defineProperty()

Object.defineProperty

Object.defineProperty()

js
var obj = Object.create({});
Object.defineProperty(obj, "foo", { value: "bar" });

Object.defineProperty(obj, "foo", { value: "baz" });
// TypeError: can't redefine non-configurable property "foo"

"foo"

js
var obj = Object.create({});
Object.defineProperty(obj, "foo", { value: "bar", configurable: true });
Object.defineProperty(obj, "foo", { value: "baz", configurable: true });

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    107. TypeError: can't delete non-configurable array element
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    109. TypeError: can't set prototype of this object
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