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copied!<p>Basically, monads are also applicative functors [1]. So, whenever you find yourself using <code>liftM</code>, <code>liftM2</code>, etc., you could chain the computation together using <code><*></code>. In some sense, you can think of applicative functors as analogous to functions. A pure function <code>f</code> can be lifted by doing <code>f <$> x <*> y <*> z</code>.</p> <p>Compared to monads, applicative functors cannot run its arguments selectively. The side effects of all the arguments will take place.</p> <pre><code>import Control.Applicative ifte condition trueClause falseClause = do c <- condition if c then trueClause else falseClause x = ifte (return True) (putStrLn "True") (putStrLn "False") ifte' condition trueClause falseClause = if condition then trueClause else falseClause y = ifte' <$> (pure True) <*> (putStrLn "True") <*> (putStrLn "False") </code></pre> <p><code>x</code> only outputs <code>True</code>, whereas <code>y</code> outputs <code>True</code> and <code>False</code> sequentially.</p> <p>[1] <a href="http://www.haskell.org/haskellwiki/Typeclassopedia" rel="noreferrer">The Typeclassopedia</a>. Highly recommended.</p> <p>[2] <a href="http://www.soi.city.ac.uk/~ross/papers/Applicative.html" rel="noreferrer">http://www.soi.city.ac.uk/~ross/papers/Applicative.html</a>. Although this is an academic paper, it's not hard to follow.</p> <p>[3] <a href="http://learnyouahaskell.com/functors-applicative-functors-and-monoids#applicative-functors" rel="noreferrer">http://learnyouahaskell.com/functors-applicative-functors-and-monoids#applicative-functors</a>. Explains the deal very well.</p> <p>[4] <a href="http://book.realworldhaskell.org/read/using-parsec.html#id652399" rel="noreferrer">http://book.realworldhaskell.org/read/using-parsec.html#id652399</a>. Shows how the monadic <code>Parsec</code> library can also be used in an applicative way.</p>

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