Defining lists in Haskell

Question

I'd like to know how to define this as a list within Haskell so that I could perform operations such as tail, reverse and length:

cars = "lamborghinis are my favourite types of car"

I've tried:

let cars = [lamborghinis,are,my,favourite,types,of,car]
let cars = ["lamborghinis","are","my","favourite","types","of","car"]
let cars = ['lamborghinis','are','my','favourite','types','of','car']

I have been using http://learnyouahaskell.com/starting-out as a tutorial as I am new to Haskell and I can't see where I'm going wrong, I thought my first attempt above would be correct as that it how it does it in the tutorial but with numbers instead of words.

The error I am getting is: parse error on input 'of.

Any ideas where I'm going wrong? Thanks.

Strings are already lists, i.e. String is a type synonym for [Char]. For example, "hello" and ['h','e','l','l','o'] are the same things. What is it that you want to do exactly? — Emil
– Emil, Commented Mar 17, 2014 at 13:26

yokto · Accepted Answer · 2014-03-17 13:26:17Z

4

let cars = "lamborghinis are my favourite types of car"

makes cars a list of characters [Char]==String and head cars should give you the first letter. This is special syntax of haskell for strings

let cars2 = ["lamborghinis","are","my","favourite","types","of","car"]

This is the normal form for defining lists and gives you a list of strings [String] and head cars should give you "lamborghinis". You can also split a sentance into words using the words function.

let cars3 = words cars

answered Mar 17, 2014 at 13:26

yokto

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kaan · Accepted Answer · 2014-03-17 13:26:34Z

1

The type String is only a type synonym for [Char].

This means that for example "Hello, you" is the same as ['H','e','l','l','o',',',' ','y','o','u']

answered Mar 17, 2014 at 13:26

kaan

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