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Inherit from SyntaxError

importance: 5

Create a class FormatError that inherits from the built-in SyntaxError class.

It should support message, name and stack properties.

Usage example:

let err = new FormatError("formatting error");

alert( err.message ); // formatting error
alert( err.name ); // FormatError
alert( err.stack ); // stack

alert( err instanceof FormatError ); // true
alert( err instanceof SyntaxError ); // true (because inherits from SyntaxError)

class FormatError extends SyntaxError {
  constructor(message) {
    super(message);
    this.name = this.constructor.name;
  }
}

let err = new FormatError("formatting error");

alert( err.message ); // formatting error
alert( err.name ); // FormatError
alert( err.stack ); // stack

alert( err instanceof SyntaxError ); // true

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