Elm Language Lists and Iteration Creating a list
Example
> listOfNumbers = [1,4,99]
[1,4,99] : List number
>
> listOfStrings = ["Hello","World"]
["Hello","World"] : List String
>
> emptyList = [] -- can be anything, we don't know yet
[] : List a
>
Under the hood, List (linked list) is constructed by the :: function (called "cons"), which takes two arguments: an element, known as the head, and a (possibly empty) list the head is prepended to.
> withoutSyntaxSugar = 1 :: []
[1] : List number
>
> longerOne = 1 :: 2 :: 3 :: []
[1,2,3] : List number
>
> nonemptyTail = 1 :: [2]
[1,2] : List number
>
List can only take values of one type, so something like [1,"abc"] is not possible. If you need this, use tuples.
> notAllowed = [1,"abc"]
==================================== ERRORS ====================================
-- TYPE MISMATCH --------------------------------------------- repl-temp-000.elm
The 1st and 2nd elements are different types of values.
8| [1,"abc"]
^^^^^
The 1st element has this type:
number
But the 2nd is:
String
Hint: All elements should be the same type of value so that we can iterate
through the list without running into unexpected values.
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