Elm Language Lists and Iteration Sorting a list by a derived value
Example
List.sortBy allows to use a function on the elements and use its result for the comparison.
> List.sortBy String.length ["longest","short","medium"]
["short","medium","longest"] : List String
-- because the lengths are: [7,5,6]
It also nicely works with record accessors:
people =
[ { name = "John", age = 43 }
, { name = "Alice", age = 30 }
, { name = "Rupert", age = 12 }
]
> List.sortBy .age people
[ { name = "Rupert", age = 12 }
, { name = "Alice", age = 30 }
, { name = "John", age = 43 }
] : List {name: String, age: number}
> List.sortBy .name people
[ { name = "Alice", age = 30 }
, { name = "John", age = 43 }
, { name = "Rupert", age = 12 }
] : List {name: String, age: number}
