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TypeError: "x" is not a non-null object( : "x" )

TypeError:    {x} (Edge)
TypeError: "x"     (Firefox)
TypeError:     : "x" (Chrome)
TypeError:  ,     (Chrome)

In this article

TypeError

?

- . null . .

, Object.create() Object.defineProperty() Object.defineProperties() , . (, ), :

js
Object.defineProperty({}, "key", 1);
// TypeError: 1 is not a non-null object

Object.defineProperty({}, "key", null);
// TypeError: null is not a non-null object

:

js
Object.defineProperty({}, "key", { value: "foo", writable: false });

WeakMap and WeakSet . .

js
var ws = new WeakSet();
ws.add("foo");
// TypeError: "foo" is not a non-null object

:

js
ws.add({ foo: "bar" });
ws.add(window);

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    112. TypeError: class constructors must be invoked with 'new'
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    118. TypeError: invalid Array.prototype.sort argument (TypeError: Array.prototype.sort argument)
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    125. TypeError: Reduce of empty array with no initial value( : )
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    128. X.prototype.y called on incompatible type
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