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- ReferenceError: "x" is not defined
- Wrong scope
- Valid cases
- Update older browsers
- SyntaxError: a declaration in the head of a for-of loop can't have an initializer
- Valid for-of loop
- SyntaxError: arguments is not valid in fields
- TypeError: 'x' is not iterable
- Iterating over Object properties
- Iterating over a generator
- Iterating over a custom iterable
- TypeError: can't assign to property "x" on "y": not an object
- Common JavaScript Errors: ReferenceError, SyntaxError, and TypeError Quiz 5 questions
Well done!
You have completed (UPI) Chapter 11: Managing Errors, Debugging, and Handling Events in JavaScript!
Instruction
Iterating over Object properties
In JavaScript, Objects are not iterable unless they implement the iterable protocol. Therefore, you cannot use for...of to iterate over the properties of an object.
const obj = { France: "Paris", England: "London" };
for (const p of obj) {
// …
} // TypeError: obj is not iterable
Instead, you have to use Object.keys or Object.entries to iterate over the properties or entries...