ClassyPrelude
map
concatMap
filter
length
singleton
null
pack
unpack
repack
fromList
toList
mapM
mapM_
stripPrefix
isPrefixOf
stripSuffix
isSuffixOf
isInfixOf
break
span
dropWhile
takeWhile
any
all
splitAt
take
drop
fold
words
unwords
lines
unlines
split
reverse
readMay
replicate
lookup
insert
delete
member
show
readFile
writeFile