concatenating a string onto all elements of [string] haskell

Question

I'm new to haskell and can't seem to figure this out. I've been using the scalpel web scraping tool and want to concatenate a bunch of URL extensions with a URL.

For example, lets say we have scraped some URL extensions into a list of strings

result =["/contact","/content"] 

and we have let

websiteURL = "www.website.com"

how do I arrive at the list ?

["www.website.com/contact", "www.website.com/content"]

Answer 1

You want to traverse your list of extensions and apply a function to each, so some kind of map is required.

The function you want to apply is to append the websiteURL string, so the answer is:

map (mappend websiteURL) result

If you didn't know the mappend function, you could find it by searching hoogle for Monoid a => a -> a -> a.

(I'll let other people generalize to more abstract types if they want...)

Answer 2

map ("aaa"++) ["bbb", "ccc"]
==> [ "aaabbb", "aaaccc" ]