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Array functions

Perform various traversal and mutation operations with arrays.

chunk()​

Creates an array of elements split into groups the length of size. If array can't be split evenly, the final chunk will be the remaining elements.

chunk(array, [size])

Arguments​

array (Array)
The array to process.
size (Number)
(Optional) The number of elements in each chunk. Default value is 1

Returns​

(Array)
The new array of arrays.

Examples​

InputExpressionResult
[1, 2, 3, 4]
chunk(@, 2)
[
    [1, 2],
    [3, 4]
]
[1, 2, 3, 4]
chunk(@, 3)
[[1, 2, 3], [4]]

compact()​

Removes all falsey values from the original array of elements. Compact will filter out false, null, 0, "", undefined, NaN.

compact(array)

Arguments​

array (Array)
The array to process.

Returns​

(Array)
The new array with filtered values.

Examples​

InputExpressionResult
[0, 1, false, "false", 2, "", 3, null]
compact(@)
[1, "false", 2, 3]

concat()​

Creates a new array of elements concatenating a target array with additional arrays and/or values.

concat(array, [values])

Arguments​

array (Array)
The array to process.
values (Any)
(Optional) The values to concatenate with original array. It could be one or many arrays and/or values.

Returns​

(Array)
The new array with concatenated elements.

Examples​

InputExpressionResult
[
    ["a", "b"],
    ["c", "d"],
    ["e", "f"]
]
concat([0], [1], [2])
["a", "b", "c", "d", "e", "f"]
[[1], 2, [3], [[4]]]
concat([0], [1], [2], [3])
[1, 2, 3, [4]]

cross_join()​

Creates a new array of paired elements by combining each element of array1 with each element of the array2. This join type is also known as cartesian join.

cross_join(array1, array2)

Arguments​

array1 (Array)
The first array to combine.
array2 (Array)
The secord array to combine.

Returns​

(Array)
The new array with combined elements.

Examples​

InputExpressionResult
{
    "array1": ["a", "b"],
    "array2": [1, 2, 3]
}
cross_join(array1, array2)
[
    ["a", 1],
    ["a", 2],
    ["a", 3],
    ["b", 1],
    ["b", 2],
    ["b", 3]
]
{
    "array1": [],
    "array2": [1, 2, 3]
}
cross_join(array1, array2)
[]
{
    "array1": ["a", "b"],
    "array2": [1, [2, 3]]
}
cross_join(array1, array2)
[
    ["a", 1],
    ["a", [2, 3]],
    ["b", 1],
    ["b", [2, 3]]
]

See also​

difference()​

Creates new array with values from array1 not included in the array2. It accepts comparator which defines how elements of the arrays are compared. The order of the result values is determined by the first array.

Aliases: difference_with()

difference(array1, array2, [comparator])

Arguments​

array1 (Array)
The array to inspect.
array2 (Array)
The values to exclude.
comparator (Expression)
(Optional) The expression invoked for each element of the arrays. The comparator is invoked with two named arguments: left, right. Default value is &left == right

Returns​

(Array)
The new array of filtered values.

Examples​

InputExpressionResult
[
    [1, 2, 3],
    [1, 2]
]
difference([0], [1])
[3]
[
    [1, 2],
    [1, 2, 3]
]
difference([0], [1])
[]
[
    ["one", "four", "three"],
    ["five", "seven"]
]
difference(
  [0],
  [1],
  &length(left)==length(right)
)
["one"]

See also​

difference_by()​

This function is similar to difference() except that it accepts iteratee which is invoked for each element of array1 and array2 to generate the criterion by which they're compared. The order of the result values is determined by the array1.

difference_by(array1, array2, [iteratee])

Arguments​

array1 (Array)
The array to inspect.
array2 (Array)
The values to exclude.
iteratee (Expression | String)
(Optional) The expression invoked for each element of the arrays. The iteratee expression is invoked with one argument: @ (current element). Default value is &@.

Returns​

(Array)
The new array of filtered values.

Examples​

InputExpressionResult
[
    [2.1, 1.2],
    [2.3, 3.4]
]
difference_by([0], [1], &floor(@))
[1.2]
[[{ "x": 2 }, { "x": 1 }], [{ "x": 1 }]]
difference_by([0], [1], 'x')
[{ "x": 2 }]

See also​

difference_with()​

Same as difference().

drop()​

Creates a new array from the original array with n elements dropped from the beginning.

drop(array, [n])

Arguments​

array (Array)
The array to query.
n (Number)
(Optional) The number of elements to drop in the original array. Default value is 1

Returns​

(Array)
The slice of array.

Examples​

InputExpressionResult
["a", "b", "c", "d", "e"]
drop(@)
["b", "c", "d", "e"]
["a", "b", "c", "d", "e"]
drop(@, 2)
["c", "d", "e"]
["a", "b", "c", "d", "e"]
drop(@, 5)
[]
["a", "b", "c", "d", "e"]
drop(@, 0)
["a", "b", "c", "d", "e"]

See also​

drop_right()​

Creates a new array from the original array with n elements dropped from the end.

drop_right(array, [n])

Arguments​

array (Array)
The array to query.
n (Number)
(Optional) The number of elements to drop in the original array from the end. Default value is 1

Returns​

(Array)
The slice of array.

Examples​

InputExpressionResult
["a", "b", "c", "d", "e"]
drop_right(@, 2)
["a", "b", "c"]

See also​

drop_right_while()​

Creates a new array from the original array with elements dropped from the end. Elements are dropped until the predicate returns falsey.

drop_right_while(array, [predicate])

Arguments​

array (Array)
The array to query.
predicate (Expression | Array | Object | String)
(Optional) The expression invoked for each iteration. The predicate is invoked with three named arguments: value, index, array. Default value is &value

Returns​

(Array)
The slice of array.

Examples​

InputExpressionResult
[
    {
        "user": "Jim",
        "active": true
    },
    {
        "user": "Ted",
        "active": false
    },
    {
        "user": "Mike",
        "active": true
    }
]
drop_right_while(
  @,
  &value.active == true
)
[
    {
        "user": "Jim",
        "active": true
    },
    {
        "user": "Ted",
        "active": false
    }
]

See also​

drop_while()​

Is similar to drop_right_while(), but it creates a new array from the original array with elements dropped from the beginning. Elements are dropped until the predicate returns falsey.

drop_while(array, [predicate])

Arguments​

array (Array)
The array to query.
predicate (Expression | Array | Object | String)
(Optional) The expression invoked for each iteration. The predicate is invoked with three named arguments: value, index, array. Default value is &value

Returns​

(Array)
The slice of array.

Examples​

InputExpressionResult
[
    {
        "user": "Jim",
        "active": true
    },
    {
        "user": "Ted",
        "active": false
    },
    {
        "user": "Mike",
        "active": true
    }
]
drop_while(
  @,
  &value.active == true
)
[
    {
        "user": "Ted",
        "active": false
    },
    {
        "user": "Mike",
        "active": true
    }
]

See also​

find_index()​

Iterates over elements of array, returning the index of the first element predicate returns truthy for.

find_index(array, [predicate], [fromIndex])

Arguments​

array (Array)
The array to inspect.
predicate (Expression | Array | Object | String)
(Optional) The expression invoked for each iteration. The predicate is invoked with three named arguments: value, index, array. Default value is &value
fromIndex (Number)
(Optional) The index to search from. Default value is 0

Returns​

(Number)
The index of the found element, else -1.

Examples​

InputExpressionResult
[
    {
        "user": "Jim",
        "active": true
    },
    {
        "user": "Ted",
        "active": false
    },
    {
        "user": "Mike",
        "active": true
    }
]
find_index(
    @,
    &value.user == 'Mike'
)
2
[
    {
        "user": "Jim",
        "active": true
    },
    {
        "user": "Ted",
        "active": false
    },
    {
        "user": "Mike",
        "active": true
    }
]
find_index(
    @,
    &value.user == 'James'
)
-1

See also​

find_last_index()​

This functions is like find_index() except that it iterates over elements of array from right to left.

find_last_index(array, [predicate], [fromIndex])

Arguments​

array (Array)
The array to inspect.
predicate (Expression | Array | Object | String)
(Optional) The expression invoked for each iteration. The predicate is invoked with three named arguments: value, index, array. Default value is &value
.
fromIndex (Number)
(Optional) The index to search from. Default value is 0

Returns​

(Number)
The index of the found element, else -1.

Examples​

InputExpressionResult
[
    {
        "user": "Jim",
        "active": true
    },
    {
        "user": "Ted",
        "active": false
    },
    {
        "user": "Mike",
        "active": true
    }
]
find_last_index(
    @,
    &value.user == 'Mike'
)
2
[
    {
        "user": "Jim",
        "active": true
    },
    {
        "user": "Ted",
        "active": false
    },
    {
        "user": "Mike",
        "active": true
    }
]
find_last_index(
    @,
    &value.user == 'Mike',
    1
)
-1

See also​

first()​

Returns the first element of an array.

Aliases: head()

first(array)

Arguments​

array (Array)
The array to query.

Returns​

(Any)
The first element of array.

Examples​

InputExpressionResult
[1, 2, 3, 4]
first(@)
1
[]
first(@)
null

See also​

flatten()​

Flattens an array for the one level deep.

flatten(array)

Arguments​

array (Array)
The array to flatten.

Returns​

(Array)
The new flattened array.

Examples​

InputExpressionResult
[1, [2, [3, [4]], 5]]
flatten(@)
[1, 2, [3, [4]], 5]
[[1], [null]]
flatten(@)
-- compare to
-- [[1], [null]] | []
[1, null]

See also​

flatten_deep​

Flattens an array recursively.

flatten_deep(array)

Arguments​

array (Array)
The array to flatten.

Returns​

(Array)
The new flattened array.

Examples​

InputExpressionResult
[1, [2, [3, [4]], 5]]
flatten_deep(@)
[1, 2, 3, 4, 5]

See also​

flatten_depth()​

Flattens an array recursively up to depth times.

flatten_depth(array, [depth])

Arguments​

array (Array)
The array to flatten.
depth (Number)
(Optional) The maximum recursion depth. Default value is 1

Returns​

(Array)
The new flattened array.

Examples​

InputExpressionResult
[1, [2, [3, [4]], 5]]
flatten_depth(@, 1)
[1, 2, [3, [4]], 5]
[1, [2, [3, [4]], 5]]
flatten_depth(@, 2)
[1, 2, 3, [4], 5]

See also​

from_pairs()​

The inverse of to_pairs() this function returns an object composed from key-value pairs.

from_pairs(pairs)

Arguments​

pairs (Array)
The key-value pairs.

Returns​

(Object)
The new object.

Examples​

InputExpressionResult
[
    ["a", 1],
    ["b", 2]
]
from_pairs(@)
{
    "a": 1,
    "b": 2
}

See also​

full_join()​

Creates a new array of paired elements by combining each element of array1 (left) with each element of the array2 (right). It accepts comparator which defines how elements of the arrays are matched. If there is no matching element in either of the arrays, null is returned. The comparator is invoked with an array of two arguments: (array1Value, array2Value).

full_join(array1, array2, comparator)

Arguments​

array1 (Array)
The first array to join.
array2 (Array)
The second array to join.
comparator (Expression)
The comparator expression invoked per each element to compare elements of arrays.

Returns​

(Array)
The new array with combined elements.

Examples​

InputExpressionResult
[
    [
        { "id": 1, "name": "a" },
        { "id": 2, "name": "b" }
    ],
    [
        { "id": 1, "value": "1" },
        { "id": 3, "value": "3" }
    ]
]
full_join([0], [1], &[0].id == [1].id)
[
    [
        { "id": 1, "name": "a" },
        { "id": 1, "value": "1" }
    ],
    [null, { "id": 3, "value": "3" }],
    [{ "id": 2, "name": "b" }, null]
]

See also​

Alias for first().

index_of()​

Gets the index at which the first occurrence of value is found in array starting from fromIndex. If fromIndex is negative, it's used as the offset from the end of array.

index_of(array, value, [fromIndex])

Arguments​

array (Array)
The array to inspect.
value (Any)
The element to search for in the array
fromIndex (Number)
(Optional) The index to search from.

Returns​

(Number)
The index of the matched value, else -1.

Examples​

InputExpressionResult
[1, 2, 1, 2, null]
index_of(@, 2)
1
[1, 2, 1, 2, null]
index_of(@, 2, 2)
3
[1, 2, 1, 2, null]
index_of(@, 2, -1)
-1
[1, 2, 1, 2, null]
index_of(@, null)
4

initial()​

Gets all elements of an original array except the last one.

initial(array)

Arguments​

array (Array)
The array to inspect.

Returns​

(Array)
The slice of array.

Examples​

InputExpressionResult
[1, 2, 3]
initial(@)
[1, 2]

inner_join()​

Creates a new array of paired elements by combining matching elements of array1 (left) and array2 (right). It accepts comparator which defines how elements of the arrays are matched. The comparator is invoked with an array of two arguments: (array1Value, array2Value).

right_join(array1, array2, comparator)

Arguments​

array1 (Array)
The first array to join.
array2 (Array)
The second array to join.
comparator (Expression)
The comparator expression invoked per each element to compare elements of arrays.

Returns​

(Array)
The new array with combined elements.

Examples​

InputExpressionResult
[
    [
        { "id": 1, "name": "a" },
        { "id": 2, "name": "b" }
    ],
    [
        { "id": 1, "value": "1" },
        { "id": 3, "value": "3" }
    ]
]
inner_join([0], [1], &[0].id == [1].id)
[
    [
        { "id": 1, "name": "a" },
        { "id": 1, "value": "1" }
    ]
]

See also​

intersection()​

Creates an array of unique values that are included in the two original arrays. As a third argument, the function accepts comparator for elements comparison. The order of result values are determined by the first array.

intersection(array1, array2, [comparator])

Arguments​

array1 (Array)
The first array to inspect.
array2 (Array)
The second array to inspect.
comparator (Expression)
(Optional) The expression invoked for each element of arrays. The comparator is invoked with two named arguments: left, right. Default value is &left==right
.

Returns​

(Array)
The new array of intersecting values.

Examples​

InputExpressionResult
[
    [2, 1],
    [2, 3]
]
intersection([0], [1])
[2]
[
    [
        { "name": "Bob", "amount": 10 },
        { "name": "Tom", "amount": 20 }
    ],
    [
        { "name": "Bob", "amount": 30 },
        { "name": "Tim", "amount": 40 }
    ]
]
intersection(
  [0],
  [1],
  &left.name == right.name
)
[{ "name": "Bob", "amount": 10 }]

See also​

intersection_by()​

This function is like intersection() except that it accepts iteratee which is invoked for each element of array1 and array2 to generate the criterion by which they're compared. The order and references of result values are determined by the array1.

intersection_by(array1, array2, [iteratee])

Arguments​

array1 (Array)
The first array to inspect.
array2 (Array)
The second array to inspect.
iteratee (Expression | String)
(Optional) The expression invoked for each element of the arrays. The iteratee expression is invoked with one argument: @ (current element). Default value is &@.

Returns​

(Array)
The new array of intersecting values.

Examples​

InputExpressionResult
[
    [2.1, 1.2],
    [2.3, 3.4]
]
intersection_by(
  [0],
  [1],
  &floor(@)
)
[2.1]
[
    [
        { "name": "Bob", "id": 1 },
        { "name": "Tom", "id": 2 }
    ],
    [
        { "name": "Bobby", "id": 1 },
        { "name": "Tim", "id": 3 }
    ]
]
intersection_by(
  [0],
  [1],
  'id'
)
[
    {
        "name": "Bob",
        "id": 1
    }
]

See also​

intersection_with()​

Alias for intersection().

join()​

Converts all elements in array into a string separated by separator.

join(array, [separator])

Arguments​

array (Array)
The array to convert.
separator (Expression)
(Optional) The element separator. Default value is ','

Returns​

(String)
The joined string.

Examples​

InputExpressionResult
[1, 2, 3, 4]
join(@)
"1,2,3,4"
["a", "b", "c"]
join(@, '-')
"a-b-c"

last()​

Gets the last element of array.

last(array)

Arguments​

array (Array)
The array to query.

Returns​

(Any)
The last element of array.

Examples​

InputExpressionResult
[1, 2, 3]
last(@)
3

last_index_of()​

This function is like index_of() except that it iterates over elements of array from right to left.

last_index_of(array, value, [fromIndex])

Arguments​

array (Array)
The array to inspect.
value (Any)
The element to search for in the array
fromIndex (Number)
(Optional) The index to search from. Default value is length(array) - 1

Returns​

(Number)
The index of the matched value, else -1.

Examples​

InputExpressionResult
[1, 2, 1, 2, null]
last_index_of(@, 2)
3
[1, 2, 1, 2, null]
last_index_of(@, 2, 2)
1

See also​

left_join()​

Creates a new array of paired elements by combining each element of array1 (left) with matching elements of the array2 (right). It accepts comparator which defines how elements of the arrays are matched. null is used, if there is no matching element in array2 (right). The comparator is invoked with an array of two arguments: (array1Value, array2Value).

left_join(array1, array2, comparator)

Arguments​

array1 (Array)
The first array to join.
array2 (Array)
The second array to join.
comparator (Expression)
The comparator expression invoked per each element to compare elements of arrays.

Returns​

(Array)
The new array with combined elements.

Examples​

InputExpressionResult
[
    [
        { "id": 1, "name": "a" },
        { "id": 2, "name": "b" }
    ],
    [
        { "id": 1, "value": "1" },
        { "id": 3, "value": "3" }
    ]
]
left_join([0], [1], &[0].id == [1].id)
[
    [
        { "id": 1, "name": "a" },
        { "id": 1, "value": "1" }
    ],
    [{ "id": 2, "name": "b" }, null]
]

See also​

nth()​

Gets the element at index n of array. If n is negative, the nth element from the end is returned.

nth(array, [n])

Arguments​

array (Array)
The array to query.
n (Number)
(Optional) The index of the element to return. Default value is 0

Returns​

(Any)
The nth element of array.

Examples​

InputExpressionResult
["a", "b", "c", "d", "e"]
nth(@, 1)
"b"
["a", "b", "c", "d", "e"]
nth(@, -2)
"d"

reverse()​

Reverses array so that the first element becomes the last, the second element becomes the second to last, and so on.

reverse(array)

Arguments​

array (Array)
The array to modify.

Returns​

(Array)
The reversed array.

Examples​

InputExpressionResult
[1, 2, 3, 4]
reverse(@)
[4, 3, 2, 1]
"Live"
reverse(@)
"eviL"

right_join()​

Creates a new array of paired elements by combining matching elements of array1 (left) with each element of the array2 (right). It accepts comparator which defines how elements of the arrays are matched. null is used, if there is no matching element in array1 (left). The comparator is invoked with an array of two arguments: (array1Value, array2Value).

right_join(array1, array2, comparator)

Arguments​

array1 (Array)
The first array to join.
array2 (Array)
The second array to join.
comparator (Expression)
The comparator expression invoked per each element to compare elements of arrays.

Returns​

(Array)
The new array with combined elements.

Examples​

InputExpressionResult
[
    [
        { "id": 1, "name": "a" },
        { "id": 2, "name": "b" }
    ],
    [
        { "id": 1, "value": "1" },
        { "id": 3, "value": "3" }
    ]
]
right_join([0], [1], &[0].id == [1].id)
[
    [
        { "id": 1, "name": "a" },
        { "id": 1, "value": "1" }
    ],
    [null, { "id": 3, "value": "3" }]
]

See also​

slice()​

Creates a slice of array from start up to, but not including, end.

slice(array, [start], [end])

Arguments​

array (Array)
The array to slice.
start (Number)
(Optional) The start position. Default value is 0
end (Number)
(Optional) The end position. Default value is length(array)

Returns​

(Array)
The new sliced array.

Examples​

InputExpressionResult
[1, 2, 3, 4, 5]
slice(@, 1, 3)
[2, 3]

tail()​

Gets all but the first element of array.

tail(array)

Arguments​

array (Array)
The array to query.

Returns​

(Array)
The new tailed array.

Examples​

InputExpressionResult
[1, 2, 3, 4, 5]
tail(@)
[2, 3, 4, 5]

take()​

Creates a slice of array with n elements taken from the beginning.

take(array, [n])

Arguments​

array (Array)
The array to query.
n (Number)
(Optional) The number of elements to take. Default value is 1

Returns​

(Array)
The slice of array.

Examples​

InputExpressionResult
[1, 2, 3, 4, 5]
take(@, 2)
[1, 2]

See also​

take_right()​

Creates a slice of array with n elements taken from the end.

take_right(array, [n])

Arguments​

array (Array)
The array to query.
n (Number)
(Optional) The number of elements to take. Default value is 1

Returns​

(Array)
The new sliced array.

Examples​

InputExpressionResult
[1, 2, 3, 4, 5]
take_right(@, 2)
[4, 5]

See also​

take_right_while()​

Creates a slice of array with elements taken from the end. Elements are taken until predicate returns falsey.

take_right_while(array, [predicate])

Arguments​

array (Array)
The array to query.
predicate (Expression | Array | Object | String)
(Optional) The expression invoked for each element of the array. The predicate is invoked with three named arguments: value, index, array. Default value is &value
.

Returns​

(Array)
The slice of array.

Examples​

InputExpressionResult
[
    {
        "user": "Jim",
        "active": true
    },
    {
        "user": "Ted",
        "active": false
    },
    {
        "user": "Mike",
        "active": false
    }
]
take_right_while(
  @,
  &!(value.active)
)
[
    {
        "user": "Ted",
        "active": false
    },
    {
        "user": "Mike",
        "active": false
    }
]

See also​

take_while()​

Creates a slice of array with elements taken from the beginning. Elements are taken until predicate returns falsey.

take_while(array, [predicate])

Arguments​

array (Array)
The array to query.
predicate (Expression | Array | Object | String)
(Optional) The expression invoked for each element of the array. The predicate is invoked with three named arguments: value, index, array. Default value is &value
.

Returns​

(Array)
The slice of array.

Examples​

InputExpressionResult
[
    {
        "user": "Jim",
        "active": true
    },
    {
        "user": "Ted",
        "active": false
    },
    {
        "user": "Mike",
        "active": false
    }
]
take_while(
  @,
  &value.active
)
[
    {
        "user": "Jim",
        "active": true
    }
]

See also​

union()​

Creates an array of unique values, in order, from given array1 and array2 using comparator for equality comparisons.

union(array1, array2, [comparator])

Arguments​

array1 (Array)
The first array to inspect.
array2 (Array)
The second array to inspect.
comparator (Expression)
(Optional) The expression invoked for each pair of element of arrays. The comparator is invoked with two named arguments: left, right. Default value is &left==right
.

Returns​

(Array)
The new array of combined values.

Examples​

InputExpressionResult
[
    [1, 2],
    [2, 2, 3]
]
union([0], [1])
[1, 2, 3]
[
    [
        { "name": "Bob", "id": 1 },
        { "name": "Tom", "id": 2 }
    ],
    [
        { "name": "Bobby", "id": 1 },
        { "name": "Tim", "id": 3 }
    ]
]
union(
  [0],
  [1],
  &left.id == right.id
)
[
    { "name": "Bob", "id": 1 },
    { "name": "Tom", "id": 2 },
    { "name": "Tim", "id": 3 }
]

See also​

union_by()​

This function is like union() except that it accepts iteratee which is invoked for each element of array1 and array2 to generate the criterion by which uniqueness is computed. Result values are chosen from the first array in which the value occurs.

union_by(array1, array2, [iteratee])

Arguments​

array1 (Array)
The first array to inspect.
array2 (Array)
The second array to inspect.
iteratee (Expression | String)
(Optional) The expression invoked for each element of the arrays. The iteratee expression is invoked with one argument @ (current element). Default value is &@.

Returns​

(Array)
The new array of combined values.

Examples​

InputExpressionResult
[
    [2.1, 1.2],
    [2.3, 3.4]
]
union_by(
  [0],
  [1],
  &floor(@)
)
[2.1, 1.2, 3.4]
[
    [
        { "name": "Bob", "id": 1 },
        { "name": "Tom", "id": 2 }
    ],
    [
        { "name": "Bobby", "id": 1 },
        { "name": "Tim", "id": 3 }
    ]
]
union_by(
  [0],
  [1],
  &length(name)
)
[
    {
        "name": "Bob",
        "id": 1
    },
    {
        "name": "Bobby",
        "id": 1
    }
]

See also​

union_with()​

Alias for union().

uniq()​

Creates a duplicate-free version of an array, using comparator for equality comparisons, in which only the first occurrence of each element is kept. The order of result values is determined by the order they occur in the array.

uniq(array, [comparator])

Arguments​

array (Array)
The array to inspect.
comparator (Expression)
(Optional) The expression invoked for each element of the array. The comparator is invoked with two named arguments: left, right. Default value is &left == right

Returns​

(Array)
The new duplicate free array.

Examples​

InputExpressionResult
[1, 2, 3, 2, 3]
uniq(@)
[1, 2, 3]
[
    { "name": "Bob", "id": 1 },
    { "name": "Tom", "id": 2 },
    { "name": "Bobby", "id": 1 },
    { "name": "Tim", "id": 3 }
]
uniq(
  @,
  &left.id == right.id
)
[
    {
        "name": "Bob",
        "id": 1
    },
    {
        "name": "Tom",
        "id": 2
    },
    {
        "name": "Tim",
        "id": 3
    }
]

See also​

uniq_by()​

This function is like uniq() except that it accepts iteratee which is invoked for each element in array to generate the criterion by which uniqueness is computed. The order of result values is determined by the order they occur in the array.

uniq_by(array, [iteratee])

Arguments​

array (Array)
The array to inspect.
iteratee (Expression | String)
(Optional) The expression invoked for each element of the array. The iteratee is invoked with one argument: value. Default value is &@
.

Returns​

(Array)
The new duplicate free array.

Examples​

InputExpressionResult
[1.1, 1.2, 2.1]
uniq_by(@, &floor(@))
[1.1, 2.1]
[
    { "name": "Bob", "id": 1 },
    { "name": "Tom", "id": 2 },
    { "name": "Bobby", "id": 1 },
    { "name": "Tim", "id": 3 }
]
uniq_by(@, 'id')
[
    {
        "name": "Bob",
        "id": 1
    },
    {
        "name": "Tom",
        "id": 2
    },
    {
        "name": "Tim",
        "id": 3
    }
]

See also​

uniq_with()​

Alias for uniq().

unzip()​

This method is like zip() except that it accepts an array of grouped elements and creates an array regrouping the elements to their pre-zip configuration.

unzip(array)

Arguments​

array (Array)
The array of grouped elements to process.

Returns​

(Array)
The new array of regrouped elements.

Examples​

InputExpressionResult
[
    ["a", 1, true],
    ["b", 2, false]
]
unzip(@)
[
    ["a", "b"],
    [1, 2],
    [true, false]
]

See also​

unzip_with()​

This function is like unzip() except that it accepts combinator to specify how regrouped values should be combined.

unzip_with(array, [combinator])

Arguments​

array (Array)
The array of grouped elements to process.
combinator (Expression)
(Optional) The expression to combine regrouped values. The combinator is invoked with an array of elements of each group. Default value is &@

Returns​

(Array)
The new array of regrouped elements.

Examples​

InputExpressionResult
[
    [1, 10, 100],
    [2, 20, 200]
]
unzip_with(@, &sum(@))
[3, 30, 300]

See also​

without()​

Creates an array excluding all given values.

without(array, value1, [value2, ...])

Arguments​

array (Array)
The array to inspect.
values (Any)
The values to exclude.

Returns​

(Array)
The new array of filtered values.

Examples​

InputExpressionResult
[2, 1, 2, 3]
without(@, 1, 2)
[3]

xor()​

Creates an array of unique values that is the symmetric difference of the given array1 and array2. It accepts comparator which is invoked to compare elements of arrays. The order of result values is determined by the order they occur in the arrays.

xor(array1, array2, [comparator])

Arguments​

array1 (Array)
The first array to inspect.
array2 (Array)
The second array to inspect.
comparator (Expression)
(Optional) The expression, invoked for each pair of elements of the arrays. The comparator is invoked with two named arguments: left, right. Default value is &left == right

Returns​

(Array)
The new array of filtered values.

Examples​

InputExpressionResult
[
    [1, 2, 3],
    [2, 4]
]
xor([0], [1])
[1, 3, 4]
[
    [
        { "name": "Bob", "id": 1 },
        { "name": "Tom", "id": 2 }
    ],
    [
        { "name": "Bobby", "id": 1 },
        { "name": "Tim", "id": 3 }
    ]
]
xor(
  [0],
  [1],
  &left.id == right.id
)
[
    {
        "name": "Tom",
        "id": 2
    },
    {
        "name": "Tim",
        "id": 3
    }
]

See also​

xor_by()​

This function is like xor() except that it accepts iteratee which is invoked for each element of array1 and array2 to generate the criterion by which by which they're compared. The order of result values is determined by the order they occur in the arrays.

xor_by(array1, array2, [iteratee])

Arguments​

array1 (Array)
The first array to inspect.
array2 (Array)
The second array to inspect.
iteratee (Expression | String)
(Optional) The expression invoked for each element of the arrays. The iteratee expression is invoked with one argument: @ (current element). Default value is &@.

Returns​

(Array)
The new array of filtered values.

Examples​

InputExpressionResult
[
    [2.1, 1.2],
    [2.3, 3.4]
]
xor_by(
  [0],
  [1],
  &floor(@)
)
[1.2, 3.4]
[
    [
        { "name": "Bob", "id": 1 },
        { "name": "Tom", "id": 2 }
    ],
    [
        { "name": "Bobby", "id": 1 },
        { "name": "Tim", "id": 3 }
    ]
]
xor_by(
  [0],
  [1],
  'id'
)
[
    {
        "name": "Tom",
        "id": 2
    },
    {
        "name": "Tim",
        "id": 3
    }
]

See also​

xor_with()​

Alias for xor().

zip()​

Creates an array of grouped elements, the first of which contains the first elements of the given arrays, the second of which contains the second elements of the given arrays, and so on.

zip(array1 [, array2 [...])

Arguments​

arrays (Array[])
The arrays to process.

Returns​

(Array)
The new array of grouped elements.

Examples​

InputExpressionResult
[
    ["a", "b"],
    [1, 2],
    [true, false]
]
zip([0], [1], [2])
[
    ["a", 1, true],
    ["b", 2, false]
]

See also​

zip_object()​

This function is like from_pairs() except that it accepts two arrays, one of property identifiers and one of corresponding values.

zip_object(props, values)

Arguments​

props (Array)
The property identifiers.
values (Array)
The property values.

Returns​

(Object)
The new object.

Examples​

InputExpressionResult
[
    ["a", "b"],
    [1, 2]
]
zip_object([0], [1])
{
    "a": 1,
    "b": 2
}

See also​

zip_object_deep()​

This function is like zip_object() except that it supports property paths.

zip_object_deep(props, values)

Arguments​

props (Array)
The property identifiers.
values (Array)
The property values.

Returns​

(Object)
The new object.

Examples​

InputExpressionResult
[
    ["a.b[0].c", "a.b[1].d"],
    [1, 2]
]
zip_object_deep([0], [1])
{
    "a": {
        "b": [{ "c": 1 }, { "d": 2 }]
    }
}

See also​

zip_with()​

This function is like zip() except that it accepts combinator to specify how grouped values should be combined.

zip_with(array1, array2, [combinator])

Arguments​

array1 (Array)
The first array to inspect.
array2 (Array)
The second array to inspect.
combinator (Expression)
(Optional) The expression to combine regrouped values. The combinator is invoked with an array of elements of each group. Default value is &@

Returns​

(Array)
The new array of grouped elements.

Examples​

InputExpressionResult
[
    [1, 2],
    [10, 20]
]
zip_with([0], [1])
[
    [1, 10],
    [2, 20]
]
[
    [1, 2],
    [10, 20]
]
zip_with([0], [1], &add([0],[1]))
[11, 22]

See also​

zip_all_with()​

This function is like zip_with() except that it groups elements from all the arrays in arrayOfArrays. The combinator is invoked with the array of all elements in a group: ([array1Item, array2Item, ...]).

zip_all_with(arrayOfArrays, [combinator])

Arguments​

arrayOfArrays (Array)
The array of arrays to inspect.
combinator (Expression)
(Optional) The expression to combine grouped values. The combinator is invoked with the array of all elements in a group. Default value is &@

Returns​

(Array)
The new array of grouped elements.

Examples​

InputExpressionResult
[
    [1, 2],
    [10, 20],
    [100, 200]
]
zip_all_with(@, &sum(@))
[111, 222]
[
    [1, 2],
    [10, 20, 30],
    [100, 200, 300, 400]
]
zip_all_with(@, &sum(@))
[111, 222, 330, 400]