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12 featuresThe __defineGetter__() and __defineSetter__() methods of objects bind a function to a property, which is called on setting or reading the property.
The Error.isError() static method checks whether a value is an Error object.
The caller and arguments properties of a non-strict mode Function object are the function that called it and the arguments it was called with. Not to be confused with the arguments variable in a function body's local scope.
JavaScript built-in methods such as, String.bold() and String.italics(), wrap strings in (often historic) HTML.
The Temporal API allows you to work with dates, times, time zones, and durations. It is more powerful than the Date API.
The await keyword, when used at the top level of a module (outside of an async function), delays parent module execution until after a promise fulfills.
The __proto__ property of objects partially exposes the prototype of an object.
The callee property of the arguments variable in a non-strict function body's local scope is the function that arguments belongs to.
The escape() and unescape() built-in Javascript methods encode and unencode strings using percent encoding, where certain characters are replaced by hexadecimal escape sequences.
The getYear() and setYear() methods of Date objects get and set the year as an offset to 1900.
The toGMTString() method of Date objects is an alias to the toUTCString() method.
The with JavaScript statement adds a given object to the chain of scopes used to evaluate names.