1 Introducción

ghci> import Data.Map as M
import qualified Data.Map as Map

2 El tipo de los diccionarios

ghci> let d1 = fromList [("Ana",5),("Juan",7),("Eva",6)]
ghci> :t d1
d1 :: Map [Char] Integer
ghci> let d2 = fromList [("Ana",5),("Eva",6),("Juan",7)]
ghci> d1 == d2
True

3 Resumen de funciones básicas

ghci> fromList [(5,"a"),(3,"b"),(5,"c")]
fromList [(3,"b"),(5,"c")]
ghci> fromList [(5,"a"),(3,"b"),(5,"c"),(3,"a")]
fromList [(3,"a"),(5,"c")]
ghci> empty
fromList []
ghci> insert 3 7 empty
fromList [(3,7)]
ghci> insert 3 'c' (fromList [(4,'a'),(6,'b'),(8,'e')])
fromList [(3,'c'),(4,'a'),(6,'b'),(8,'e')]
ghci> insert 6 'c' (fromList [(4,'a'),(6,'b'),(8,'e')])
fromList [(4,'a'),(6,'c'),(8,'e')]
ghci> M.null (fromList [])
True
ghci> M.null (fromList [(3,2)])
False
ghci> size empty
0
ghci> size (fromList [(4,'a'),(5,'b'),(2,'e')])
3
ghci> size (fromList [(4,'a'),(5,'b'),(2,'e'),(4,'a')])
3
ghci> size (fromList [(4,'a'),(5,'b'),(2,'e'),(4,'c')])
3
ghci> singleton 'd' 4
fromList [('d',4)]
ghci> M.lookup 5 (fromList [(4,'a'),(5,'b'),(2,'e')])
Just 'b'
ghci> M.lookup 7 (fromList [(4,'a'),(5,'b'),(2,'e')])
Nothing
ghci> member 5 (fromList [(4,'a'),(5,'b'),(2,'e')])
True
ghci> member 7 (fromList [(4,'a'),(5,'b'),(2,'e')])
False
ghci> M.map (+1) (fromList [(8,4),(3,8),(7,3),(6,7)])
fromList [(3,9),(6,8),(7,4),(8,5)]
ghci> M.filter (>5) (fromList [("b",4),("e",8),("d",3),("a",7)])
fromList [("a",7),("e",8)]
ghci> toList (fromList [(1,7),(3,5),(2,8)])
[(1,7),(2,8),(3,5)]
ghci> keys (fromList [(1,7),(3,5),(2,8)])
[1,2,3]
ghci> elems (fromList [(1,7),(3,5),(2,8)])
[7,8,5]
ghci> fromListWith (++) [(5,"a"),(3,"b"),(5,"c")]
fromList [(3,"b"),(5,"ca")]
ghci> fromListWith (++) [(5,"a"),(3,"b"),(5,"c"),(3,"a")]
fromList [(3,"ab"),(5,"ca")]
ghci> fromListWith (-) [(5,4),(3,6),(5,2),(3,1)]
fromList [(3,-5),(5,-2)]
ghci> insertWith (++) 7 "d" (fromList [(5,"a"), (3,"b")])
fromList [(3,"b"),(5,"a"),(7,"d")]
ghci> insertWith (++) 3 "d" (fromList [(5,"a"), (3,"b")])
fromList [(3,"db"),(5,"a")]
ghci> insertWith (*) 3 2 (fromList [(5,6), (3,4)])
fromList [(3,8),(5,6)]
ghci> insertWith (*) 3 2 empty
fromList [(3,2)]

4 Funciones sobre diccionarios

5 Referencia