Array.every
static
boolean
Array.every
(
a
,
f
,
o
)
Executes the supplied function on each item in the array.
Iteration stops if the supplied function does not return
a truthy value.
- Parameters:
-
a <Array>the array to iterate. -
f <Function>the function to execute on each item. -
o <object>Optional context object.
- Returns:
boolean - true if every item in the array returns true from the supplied function.
Array.filter
static
Array
Array.filter
(
a
,
f
,
o
)
Executes the supplied function on each item in the array. Returns a new array
containing the items for which the supplied function returned a truthy value.
- Parameters:
-
a <Array>Array to filter. -
f <Function>Function to execute on each item. -
o <Object>Optional context object.
- Returns:
Array - Array of items for which the supplied function returned a truthy value (empty if it never returned a truthy value).
Array.find
static
object
Array.find
(
a
,
f
,
o
)
Executes the supplied function on each item in the array,
searching for the first item that matches the supplied
function.
- Parameters:
-
a <Array>the array to search. -
f <Function>the function to execute on each item. Iteration is stopped as soon as this function returns true on an item. -
o <object>Optional context object.
- Returns:
object - the first item that the supplied function returns true for, or null if it never returns true.
Array.forEach
void
Array.forEach
(
)
forEach is an alias of Array.each. This is part of the
collection module.
Array.grep
static
Array
Array.grep
(
a
,
pattern
)
Iterates over an array, returning a new array of all the elements
that match the supplied regular expression
- Parameters:
-
a <Array>a collection to iterate over. -
pattern <RegExp>The regular expression to test against each item.
- Returns:
Array - All the items in the collection that produce a match against the supplied regular expression. If no items match, an empty array is returned.
Array.lastIndexOf
static
Number
Array.lastIndexOf
(
a
,
val
,
fromIndex
)
Returns the index of the last item in the array that contains the specified
value, or -1 if the value isn't found.
- Parameters:
-
a <Array>Array to search in. -
val <any>Value to search for. -
fromIndex <Number>(optional) Index at which to start searching backwards. Defaults to the array's length - 1. If negative, it will be taken as an offset from the end of the array. If the calculated index is less than 0, the array will not be searched and -1 will be returned.
- Returns:
Number - Index of the item that contains the value, or -1 if not found.
Array.map
static
Array
Array.map
(
a
,
f
,
o
)
Executes the supplied function on each item in the array.
- Parameters:
-
a <Array>the array to iterate. -
f <Function>the function to execute on each item. -
o <object>Optional context object.
- Returns:
Array - A new array containing the return value of the supplied function for each item in the original array.
Array.partition
static
object
Array.partition
(
a
,
f
,
o
)
Partitions an array into two new arrays, one with the items
that match the supplied function, and one with the items that
do not.
- Parameters:
-
a <Array>a collection to iterate over. -
f <Function>a function that will receive each item in the collection and its index. -
o <object>Optional execution context of f.
- Returns:
object - An object with two members, 'matches' and 'rejects', that are arrays containing the items that were selected or rejected by the test function (or an empty array).
Array.reduce
static
any
Array.reduce
(
a
,
init
,
f
,
o
)
Executes the supplied function on each item in the array.
Reduce "folds" the array into a single value. The callback
function receives four arguments:
the value from the previous callback call (or the initial value),
the value of the current element, the current index, and
the array over which iteration is occurring.
- Parameters:
-
a <Array>the array to iterate. -
init <any>The initial value to start from. -
f <Function>the function to execute on each item. It is responsible for returning the updated value of the computation. -
o <object>Optional context object.
- Returns:
any - A value that results from iteratively applying the supplied function to each element in the array.
Array.reject
static
Array
Array.reject
(
a
,
f
,
o
)
The inverse of filter. Executes the supplied function on each item.
Returns a new array containing the items that the supplied
function returned *false* for.
- Parameters:
-
a <Array>the array to iterate. -
f <Function>the function to execute on each item. -
o <object>Optional context object.
- Returns:
Array - The items on which the supplied function returned false.
Array.unique
static
Array
Array.unique
(
a
)
Returns a copy of the specified array with duplicate items removed.
- Parameters:
-
a <Array>Array to dedupe.
- Returns:
Array - Copy of the array with duplicate items removed.
Array.zip
static
array
Array.zip
(
a
,
a2
)
Creates an array of arrays by pairing the corresponding
elements of two arrays together into a new array.
- Parameters:
-
a <Array>a collection to iterate over. -
a2 <Array>another collection whose members will be paired with members of the first parameter.
- Returns:
array - An array of arrays formed by pairing each element of the first collection with an item in the second collection having the corresponding index.