A description of how to sort values of a particular type.

Create a custom Sorter by defining how to order two values.

Reverse a sorter.

Sort.list Sort.alphabetical [ "b", "c", "a" ]
--> [ "a", "b", "c" ]


Sort.list (Sort.reverse Sort.alphabetical) [ "b", "c", "a" ]
--> [ "c", "b", "a" ]

Sort by a derived value.

One way to use this is with collections of records:

Sort.list (Sort.by .name String.alphabetical)
  [ { name = "Bo" }, { name = "Amy" }, { name = "Cam" } ]
--> [ { name = "Amy" }, { name = "Bo" }, { name = "Cam" } ]

Another use is for unwrapping union type constructors:

import Sort exposing (Sorter)


type Username
    = Username String


alphabetical : Sorter Username
alphabetical =
    Sort.by (\(Username str) -> str) Sort.alphabetical

Determine an Order for two values, based on the given Sorter

Sort strings alphabetically.

Sort.list Sort.alphabetical [ "cabbage", "banana", "apple" ]
--> [ "apple", "banana", "cabbage" ]

To sort in reverse alphabetical order, use Sort.reverse

Sort.list (Sort.reverse Sort.alphabetical) [ "cabbage", "banana", "apple" ]
--> [ "cabbage",  "banana", "apple" ]

Sort numbers from lowest to highest.

Sort.list Sort.increasing [ 4, 7, 2 ]
--> [ 2, 4, 7 ]

To sort decreasing, use Sort.reverse

Sort.list (Sort.reverse Sort.increasing) [ 4, 7, 2 ]
--> [ 7, 4, 2 ]

Sort a list using a Sorter.

This can be used as an alternative to List.sort, List.sortBy, and List.sortWith.

Sort.list Sort.alphabetical [ "foo", "bar", "baz" ]
    --> [ "baz", "bar", "foo" ]

You can also use Sort.by and Sort.reverse to transform sorters:

-- Sort users by name, in reverse alphabetical order
Sort.list
    (Sort.by .name (Sort.reverse Sort.alphabetical))
    users