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copied!<p>There's a lot of things you could possibly mean. For example, if you want a few copies of a single value, you can use <code>replicate</code>, defined in the Prelude:</p> <pre><code>replicate :: Int -> a -> [a] replicate 0 x = [] replicate n | n < 0 = undefined | otherwise = x : replicate (n-1) x </code></pre> <p>In ghci:</p> <pre><code>Prelude> replicate 4 ("Haskell", 2) [("Haskell",2),("Haskell",2),("Haskell",2),("Haskell",2)] </code></pre> <p>Alternately, perhaps you actually want to do some IO to determine the list. Then a simple loop will do:</p> <pre><code>getListFromUser = do putStrLn "keep going?" s <- getLine case s of 'y':_ -> do putStrLn "enter a value" v <- readLn vs <- getListFromUser return (v:vs) _ -> return [] </code></pre> <p>In ghci:</p> <pre><code>*Main> getListFromUser :: IO [(String, Int)] keep going? y enter a value ("Haskell",2) keep going? y enter a value ("Prolog",4) keep going? n [("Haskell",2),("Prolog",4)] </code></pre> <p>Of course, this is a particularly crappy user interface -- I'm sure you can come up with a dozen ways to improve it! But the pattern, at least, should shine through: you can use values like <code>[]</code> and functions like <code>:</code> to construct lists. There are many, many other higher-level functions for constructing and manipulating lists, as well.</p> <p>P.S. There's nothing particularly special about lists of tuples (as compared to lists of other things); the above functions display that by never mentioning them. =)</p>

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