For example: newfile :: FilePath -> IO Bool newfile x | length x <= 0 = retur开发者_Python百科n False
What is a good way for a Haskell function to check a number of different conditions and return an error message on a failure?
I am attempting to create a stack of monad transformers and am having trouble getting the correct type signatures for my functions. (I\'m still pretty new to Haskell)
开发者_C百科I\'m needing some Ints to use as seed to random number generation and so I wanted to use the old trick of using the system time as seed.
I have function f with signature f :: [a] -> StateT Int Reader b [c], and f\' with signature f\' :: a -> StateT Int Reader b [c]
I have an Int that i want to split into it\'s individual numb开发者_开发知识库erswhich ideally would be contained in a list, which i can then process further. So i would like something like this:
I\'ve been playing with newtype wrappers for my indexes to avoid 开发者_JAVA技巧bugs, and I have some code like this:
I\'m reading Real World Haskell Pg 151, and I\'ve stared at the following passage for over an hour: Recall that String is a synonym for
Is there a way to use the TDFA implementation of Regex with the functions in Text.Regex such as subRegex? The documentation says that Text.Regex must use the POSIX implemen开发者_运维技巧tation only.S
I\'ve managed to use Parsec to parse a String, but cannot manage to do the same with a ByteString. How can I make Parsec work with ByteStrings without manually converting them to Strings?
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