Hi,
I'm beginning to study Haskell, For the following
a = [1,2,3]
b = "there"
do x <- a
y <- b
return (x , y)
Winhugs cannot run it. Gives
Syntax error in input (unexpected backslash ( lambda))
Your problem is that you're using monads to grab the contents of a and b, while a and b are not monadic...
They *are* actually monadic, just perhaps not the monad the OP expects. This code should compile and produce the cartesian product of the numbers {1, 2, 3} and the characters {t,h,e,r,e}. I'm not sure what would cause the given error -- it may be a layout problem (the indention is wrong but it might just be the mailer). ___ ___ _ / _ \ /\ /\/ __(_) / /_\// /_/ / / | | GHC Interactive, version 6.2.2, for Haskell 98. / /_\\/ __ / /___| | http://www.haskell.org/ghc/ \____/\/ /_/\____/|_| Type :? for help. Loading package base ... linking ... done. Prelude> let a = [1,2,3] Prelude> let b = "there" Prelude> do { x <- a; y <- b; return (x,y) } [(1,'t'),(1,'h'),(1,'e'),(1,'r'),(1,'e'),(2,'t'),(2,'h'),(2,'e'),(2,'r'),(2,'e') ,(3,'t'),(3,'h'),(3,'e'),(3,'r'),(3,'e')] Prelude>