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- Description of syntactic sugar
Summary of the various uses of syntactic sugar in Haskell
[edit] Functions
- For more information, see the chapter More on functions
| description |
sweet |
unsweet |
| sections |
(+2)
(3-)
|
\x -> x + 2
\x -> 3 - x
|
- For more information, see the chapters Lists and tuples and More about lists
| description |
sweet |
unsweet |
| lists |
[1,2,3]
|
1:2:3:[]
|
| arithmetic sequences |
[1..5]
[1,3..9]
[1..]
[1,3..]
|
enumFromTo 1 5
enumFromThenTo 1 3 9
enumFrom 1
enumFromThen 1 3
|
| list comprehensions |
[ x | (x,y) <- foos, x < 2 ]
|
let ok (x,y) = if x < 2 then [x] else []
in concatMap ok foos
|
[edit] Records
[edit] Do and proc notation
- For more information, see the chapters Understanding monads and Arrows
| description |
sweet |
unsweet |
| Sequencing |
do putStrLn "one"
putStrLn "two"
|
putStrLn "one" >>
putStrLn "two"
|
| Monadic binding |
do x <- getLine
putStrLn $ "You typed: " ++ x
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getLine >>= \x ->
putStrLn $ "You typed: " ++ x
|
| Let binding |
do let f xs = xs ++ xs
putStrLn $ f "abc"
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let f xs = xs ++ xs
in putStrLn $ f "abc"
|
[edit] Layout
- For more information on layout, see the chapter on Indentation
