The slice() method of Array instances returns a shallow copy of a portion of an array into a new array object selected from start to end (end not included) where start and end represent the index of items in that array. The original array will not be modified.

The at() method of TypedArray instances takes an integer value and returns the item at that index, allowing for positive and negative integers. Negative integers count back from the last item in the typed array. This method has the same algorithm as Array.prototype.at().

The reduce() method of Array instances executes a user-supplied "reducer" callback function on each element of the array, in order, passing in the return value from the calculation on the preceding element. The final result of running the reducer across all elements of the array is a single value.

The Reflect.has() static method is like the in operator, but as a function.

The formatRange() method of Intl.DateTimeFormat instances formats a date range in the most concise way based on the locales and options provided when instantiating this Intl.DateTimeFormat object.

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The values() method of Map instances returns a new map iterator object that contains the values for each element in this map in insertion order.

The size accessor property of Map instances returns the number of elements in this map.

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