The JavaScript exception "is not a function" occurs when there was an attempt to call a value from a function, but the value is not actually a function.

The JavaScript exception "BigInt value can't be serialized in JSON" occurs when a BigInt is encountered in JSON.stringify with no custom serialization method provided.

The JavaScript exception "Iterator constructor can't be used directly" or "AsyncIterator constructor can't be used directly" occurs when you try to use the Iterator() or AsyncIterator() constructors directly to create instances. These constructors are abstract classes and should only be inherited from.

The JavaScript exception "return not in function" occurs when a return statement is called outside of a function.

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The JavaScript exception "TypeError: can't set prototype: it would cause a prototype chain cycle" occurs when an object's prototype is set to an object such that the prototype chain becomes circular (a and b both have each other in their prototype chains).

The JavaScript exception "property is non-configurable and can't be deleted" occurs when it was attempted to delete a property, but that property is non-configurable.