Arrays and list functions

Use these functions to make interaction with arrays, lists, and strings easier.

Count only null

The countOnlyNull function is used to count the number of null values in a list.

Syntax

{%= countOnlyNull(array) %}

Example

{%= countOnlyNull([4,0,1,6,0,0]) %}

Returns 3.

Count With Null

The countWithNull function is used to count all the elements of a list including null values.

Syntax

{%= countWithNull(array) %}

Example

{%= countOnlyNull([4,0,1,6,0,0]) %}

Returns 6.

Distinct

The distinct function is used to get values from an array or list with duplicate values removed.

Syntax

{%= distinct(array) %}

Example

The following operation specifies people who have placed orders in more than one store.

{%= distinct(person.orders.storeId).count() > 1 %}

Distinct Count With Null

The distinctCountWithNull function is used to count the number of different values in a list including the null values.

Syntax

{%= distinctCountWithNull(array) %}

Example

{%= distinctCountWithNull([10,2,10,null]) %}

Returns 3.

First item

The head function is used to return the first item in an array or list.

Syntax

{%= head(array) %}

Example

The following operation returns the first of the top five orders with the highest price. More information about the topN function can be found in the first n in array section.

{%= head(topN(orders,price, 5)) %}

First n in array

The topN function is used to return the first N items in an array, when sorted in ascending order based on the given numerical expression.

Syntax

{%= topN(array, value, amount) %}

Example

The following operation returns the first five orders with the lowest price.

{%= topN(orders,price, 5) %}

In

The in function is used to determine if an item is a member of an array or list.

Syntax

{%= in(value, array) %}

Example

The following operation defines people with birthdays in March, June, or September.

{%= in (person.birthMonth, [3, 6, 9]) %}

Includes

The includes function is used to determine if an array or list contains a given item.

Syntax

{%= includes(array,item) %}

Example

The following operation defines people whose favorite color includes red.

{%= includes(person.favoriteColors,"red") %}

Intersects

The intersects function is used to determine if two arrays or lists have at least one common member.

Syntax

{%= intersects(array1, array2) %}

Example

The following operation defines people whose favorite colors include at least one of red, blue, or green.

{%= intersects(person.favoriteColors,["red", "blue", "green"]) %}

Last n in array

The bottomN function is used to return the last N items in an array, when sorted in ascending order based on the given numerical expression.

Syntax

{%= bottomN(array, value, amount) %}

Example

The following operation returns the last five orders with the highest price.

{%= bottomN(orders,price, 5) %}

Not in

The notIn function is used to determine if an item is not a member of an array or list.

Syntax

{%= notIn(value, array) %}

Example

The following operation defines people with birthdays that are not in March, June, or September.

{%= notIn(person.birthMonth ,[3, 6, 9]) %}

Subset of

The subsetOf function is used to determine if a specific array (array A) is a subset of another array (array B). In other words, that all elements in array A are elements of array B.

Syntax

{%= subsetOf(array1, array2) %}

Example

The following operation defines people who have visited all of their favorite cities.

{%= subsetOf(person.favoriteCities,person.visitedCities) %}

Superset of

The supersetOf function is used to determine if a specific array (array A) is a superset of another array (array B). In other words, that array A contains all elements in array B.

Syntax

{%= supersetOf(array1, array2) %}

Example

The following operation defines people who have eaten sushi and pizza at least once.

{%= supersetOf(person.eatenFoods,["sushi", "pizza"] %}