NLP.GenI.General

This module provides some very generic, non-GenI specific functions on strings, trees and other miscellaneous odds and ends. Whenever possible, one should try to replace these functions with versions that are available in the standard libraries, or the Haskell platform ones, or on hackage.

IO

ePutStr :: String -> IO ()

putStr on stderr

ePutStrLn :: String -> IO ()

eFlush :: IO ()

Strict readFile

readFile' :: FilePath -> IO String

Using readFile' can be a good idea if you're dealing with not-so-huge files (i.e. where you don't want lazy evaluation), because it ensures that the handles are closed. No more ``too many open files''

lazySlurp :: ForeignPtr Word8 -> Int -> Int -> IO String

Timeouts

withTimeout

Arguments

:: Integer

-> IO a

action to run upon timing out

-> IO a

main action to run

-> IO a

exitTimeout :: IO ()

Like exitFailure, except that we return with a code that we reserve for timing out

Strings

dropTillIncluding :: Char -> String -> String

Drop all characters up to and including the one in question

trim :: String -> String

toUpperHead :: String -> String

Make the first character of a string upper case

toLowerHead :: String -> String

Make the first character of a string lower case

toAlphaNum :: String -> [AlphaNum]

An alphanumeric sort is one where you treat the numbers in the string as actual numbers. An alphanumeric sort would put x2 before x100, because 2 < 10, wheraeas a naive sort would put it the other way around because the characters 1 < 2. To sort alphanumerically, just 'sortBy (comparing toAlphaNum)'

Triples

fst3 :: (a, b, c) -> a

snd3 :: (a, b, c) -> b

thd3 :: (a, b, c) -> c

Lists

equating :: Eq b => (a -> b) -> a -> a -> Bool

comparing :: Ord b => (a -> b) -> a -> a -> Ordering

map' :: (a -> b) -> [a] -> [b]

A strict version of map

wordsBy :: Eq a => a -> [a] -> [[a]]

A generic version of the Data.List.words TODO: replace by version from split

boundsCheck :: Int -> [a] -> Bool

Makes sure that index s is in the bounds of list l. Surely there must be some more intelligent way to deal with this.

isEmptyIntersect :: Eq a => [a] -> [a] -> Bool

True if the intersection of two lists is empty.

groupByFM :: Ord b => (a -> b) -> [a] -> Map b [a]

Serves the same function as groupBy. It groups together items by some property they have in common. The difference is that the property is used as a key to a Map that you can lookup.

multiGroupByFM :: Ord b => (a -> [b]) -> [a] -> Map b [a]

Same as groupByFM, except that we let an item appear in multiple groups. The fn extracts the property from the item, and returns multiple results in the form of a list

insertToListMap :: Ord b => b -> a -> Map b [a] -> Map b [a]

groupAndCount :: (Eq a, Ord a) => [a] -> [(a, Int)]

Convert a list of items into a list of tuples (a,b) where a is an item in the list and b is the number of times a in occurs in the list.

combinations :: [[a]] -> [[a]]

mapMaybeM :: Monad m => (a -> m (Maybe b)) -> [a] -> m [b]

repList :: (a -> Bool) -> (a -> a) -> [a] -> [a]

Return the list, modifying only the first matching item.

Trees

mapTree' :: (a -> b) -> Tree a -> Tree b

Strict version of mapTree (for non-strict, just use fmap)

filterTree :: (a -> Bool) -> Tree a -> [a]

Like filter, except on Trees. Filter might not be a good name, though, because we return a list of nodes, not a tree.

treeLeaves :: Tree a -> [a]

The leaf nodes of a Tree

preTerminals :: Tree a -> [(a, a)]

Return pairs of (parent, terminal)

repNode

Arguments

:: (Tree a -> Tree a)

replacement function

-> (Tree a -> Bool)

filtering function

-> Tree a

-> Maybe (Tree a)

repNode fn filt t returns a version of t in which the first node which filt matches is transformed using fn.

repAllNode :: (Tree a -> Tree a) -> (Tree a -> Bool) -> Tree a -> Tree a

Like repNode except that it performs the operations on all nodes that match and doesn't care if any nodes match or not

listRepNode

Arguments

:: (Tree a -> Tree a)

replacement function

-> (Tree a -> Bool)

filtering function

-> [Tree a]

nodes

-> ([Tree a], Bool)

Like repNode but on a list of tree nodes

repNodeByNode

Arguments

:: (a -> Bool)

which node?

-> a

-> Tree a

-> Tree a

Replace a node in the tree in-place with another node; keep the children the same. If the node is not found in the tree, or if there are multiple instances of the node, this is treated as an error.

Intervals

type Interval = (Int, Int)

(!+!) :: Interval -> Interval -> Interval

Add two intervals

ival :: Int -> Interval

ival x builds a trivial interval from x to x

showInterval :: Interval -> String

Bit vectors

type BitVector = Integer

showBitVector :: Int -> BitVector -> String

displays a bit vector, using a minimum number of bits

Bugs

geniBug :: String -> a

errors specifically in GenI, which is very likely NOT the user's fault.