John Wicket wrote:
On 9/24/07, Sam Hughes [EMAIL PROTECTED] wrote:
John Wicket wrote:
I am still in an imperative way of thinking. In this example here; how
would I call putStrLn and then set the function with a value. Eg:
aa :: String - IO ()
aa instr = do
putStrLn abc
putStrLn abc
John Wicket wrote:
Sorry, I was actually trying to use this as an example for something
more complicated I am trying to do. In this example, why would the
inferred type be IO ()
aa :: String - String
aa instr = do
putStrLn abc
putStrLn abc
return Az
Couldn't match expected type
On Mon, 24 Sep 2007, John Wicket wrote:
I am still in an imperative way of thinking. In this example here; how
would I call putStrLn and then set the function with a value. Eg:
aa :: String - IO ()
aa instr = do
putStrLn abc
putStrLn abc
return 123
The article
Well aa isn't returning a string. It's returning a function for
later evaluation which encapsulates the string. It's like
driving anywhere in California. You can't get there following
the road signs unless you've driven there once before. In this
case the road signs say return a string but
I am still in an imperative way of thinking. In this example here; how
would I call putStrLn and then set the function with a value. Eg:
aa :: String - IO ()
aa instr = do
putStrLn abc
putStrLn abc
return 123
--- The error I am getting.
Couldn't match expected type `()' against
John Wicket wrote:
I am still in an imperative way of thinking. In this example here; how
would I call putStrLn and then set the function with a value. Eg:
aa :: String - IO ()
aa instr = do
putStrLn abc
putStrLn abc
return 123
--- The error I am getting.
Couldn't match expected
Sorry, I was actually trying to use this as an example for something more
complicated I am trying to do. In this example, why would the inferred type
be IO ()
aa :: String - String
aa instr = do
putStrLn abc
putStrLn abc
return Az
Couldn't match expected type `[t]' against inferred type
