How to print the same char n times in Haskell

Question

I would like to print a char underlining a String n times, with n the length of the String in Haskell.

How should I do this?

My String is: \"Available Chars (x)\

Answer 1

Use replicate:

underline :: String -> String
underline = flip replicate '-' . length

This will give you a string which is n times the character '-' where n is the length of the input string. It is the same as:

underline = map $ const '-'

You can then use it like this (if for example yourString = "Available Chars (111)"):

> putStrLn yourString >> putStrLn (underline yourString)
Available Chars (111)
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