3.5. Enumerable Objects and Iterator Functions
Prototype brings higher-order functions to mainstream JavaScript in the form of enumerable objects. The Enumeration interface represents a collection objects and exposes a set of functions that allow the manipulation of these objects using iterator functions.
An iterator function is a normal JavaScript function of the form:
var iterator = function(value,index) { ... }
where the arguments to this function represent a value from the collection and the index that the value is at within the collection. Armed with an iterator function, we may make use of the functions on Enumerable.
each | Calls the iterator on each element |
all | Returns true if all iterators return true |
any | Returns true if any iterator returns true |
collect | Maps the iterator across the collection, returning a collection of results in the same order |
detect | Returns first element for which the iterator returns true |
entries | Returns an array of elements |
find | Same as detect |
findAll | Returns all elements for which the iterator returns true |
grep | Returns all elements for which a regular expression matches |
include | Returns true if a given object is in the collection |
inject | Collapses the collection into a value using the iterator with an additional initial accumulating parameter as an accumulator. |
invoke | Invokes a member function (passing in arguments) on each element in the collection |
map | Same as collect |
max | Returns the maximum element |
member | Same as include ... |
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