<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html> <head> <!-- Generated by HsColour, http://www.cs.york.ac.uk/fp/darcs/hscolour/ --> <title>Data/List/Split.hs</title> <link type='text/css' rel='stylesheet' href='hscolour.css' /> </head> <body> <pre><a name="line-1"></a><span class='hs-comment'>-----------------------------------------------------------------------------</span> <a name="line-2"></a><span class='hs-comment'>-- |</span> <a name="line-3"></a><span class='hs-comment'>-- Module : Data.List.Split</span> <a name="line-4"></a><span class='hs-comment'>-- Copyright : (c) Brent Yorgey, Louis Wasserman 2008</span> <a name="line-5"></a><span class='hs-comment'>-- License : BSD-style (see LICENSE)</span> <a name="line-6"></a><span class='hs-comment'>-- Maintainer : Brent Yorgey <byorgey@gmail.com></span> <a name="line-7"></a><span class='hs-comment'>-- Stability : experimental</span> <a name="line-8"></a><span class='hs-comment'>-- Portability : unportable (GADTs, Rank2Types)</span> <a name="line-9"></a><span class='hs-comment'>--</span> <a name="line-10"></a><span class='hs-comment'>-- The "Data.List.Split" module contains a wide range of strategies</span> <a name="line-11"></a><span class='hs-comment'>-- for splitting lists with respect to some sort of delimiter, mostly</span> <a name="line-12"></a><span class='hs-comment'>-- implemented through a unified combinator interface. The goal is to</span> <a name="line-13"></a><span class='hs-comment'>-- be flexible yet simple. Scroll past the Synopsis for usage,</span> <a name="line-14"></a><span class='hs-comment'>-- examples, and detailed documentation of all exported functions. If</span> <a name="line-15"></a><span class='hs-comment'>-- you want to learn about the implementation, see</span> <a name="line-16"></a><span class='hs-comment'>-- "Data.List.Split.Internals".</span> <a name="line-17"></a><span class='hs-comment'>--</span> <a name="line-18"></a><span class='hs-comment'>-- A darcs repository containing the source (including a module with</span> <a name="line-19"></a><span class='hs-comment'>-- over 40 QuickCheck properties) can be found at</span> <a name="line-20"></a><span class='hs-comment'>-- <<a href="http://code.haskell.org/~byorgey/code/split">http://code.haskell.org/~byorgey/code/split</a>>.</span> <a name="line-21"></a><span class='hs-comment'>--</span> <a name="line-22"></a><span class='hs-comment'>-----------------------------------------------------------------------------</span> <a name="line-23"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>List</span><span class='hs-varop'>.</span><span class='hs-conid'>Split</span> <span class='hs-layout'>(</span> <a name="line-24"></a> <a name="line-25"></a> <span class='hs-comment'>-- * Getting started</span> <a name="line-26"></a> <span class='hs-comment'>-- $started</span> <a name="line-27"></a> <a name="line-28"></a> <span class='hs-comment'>-- * Convenience functions</span> <a name="line-29"></a> <span class='hs-comment'>-- $conv</span> <a name="line-30"></a> <a name="line-31"></a> <span class='hs-varid'>splitOn</span> <a name="line-32"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>splitOneOf</span> <a name="line-33"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>splitWhen</span> <a name="line-34"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>sepBy</span> <a name="line-35"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>sepByOneOf</span> <a name="line-36"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>endBy</span> <a name="line-37"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>endByOneOf</span> <a name="line-38"></a> <a name="line-39"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>unintercalate</span> <a name="line-40"></a> <a name="line-41"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>wordsBy</span> <a name="line-42"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>linesBy</span> <a name="line-43"></a> <a name="line-44"></a> <span class='hs-comment'>-- * Other splitting methods</span> <a name="line-45"></a> <span class='hs-comment'>-- $other</span> <a name="line-46"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>splitEvery</span> <a name="line-47"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>chunk</span> <a name="line-48"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>splitPlaces</span> <a name="line-49"></a> <a name="line-50"></a> <span class='hs-comment'>-- * Splitting combinators</span> <a name="line-51"></a> <span class='hs-comment'>-- $comb</span> <a name="line-52"></a> <a name="line-53"></a> <span class='hs-layout'>,</span> <span class='hs-conid'>Splitter</span> <a name="line-54"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>defaultSplitter</span> <a name="line-55"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>split</span> <a name="line-56"></a> <a name="line-57"></a> <span class='hs-comment'>-- ** Basic strategies</span> <a name="line-58"></a> <span class='hs-comment'>-- $basic</span> <a name="line-59"></a> <a name="line-60"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>oneOf</span> <a name="line-61"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>onSublist</span> <a name="line-62"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>whenElt</span> <a name="line-63"></a> <a name="line-64"></a> <span class='hs-comment'>-- ** Strategy transformers</span> <a name="line-65"></a> <span class='hs-comment'>-- $transform</span> <a name="line-66"></a> <a name="line-67"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>dropDelims</span> <a name="line-68"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>keepDelimsL</span> <a name="line-69"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>keepDelimsR</span> <a name="line-70"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>condense</span> <a name="line-71"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>dropInitBlank</span> <a name="line-72"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>dropFinalBlank</span> <a name="line-73"></a> <a name="line-74"></a> <span class='hs-comment'>-- ** Derived combinators</span> <a name="line-75"></a> <span class='hs-comment'>-- $derived</span> <a name="line-76"></a> <a name="line-77"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>dropBlanks</span> <a name="line-78"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>startsWith</span> <a name="line-79"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>startsWithOneOf</span> <a name="line-80"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>endsWith</span> <a name="line-81"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>endsWithOneOf</span> <a name="line-82"></a> <a name="line-83"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span> <a name="line-84"></a> <a name="line-85"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>List</span><span class='hs-varop'>.</span><span class='hs-conid'>Split</span><span class='hs-varop'>.</span><span class='hs-conid'>Internals</span> <a name="line-86"></a> <a name="line-87"></a><span class='hs-comment'>-- $started</span> <a name="line-88"></a><span class='hs-comment'>-- To get started, you should take a look at the functions 'splitOn',</span> <a name="line-89"></a><span class='hs-comment'>-- 'splitWhen', 'sepBy', 'endBy', 'splitEvery', 'splitPlaces', and</span> <a name="line-90"></a><span class='hs-comment'>-- other functions listed in the next two sections. These functions</span> <a name="line-91"></a><span class='hs-comment'>-- implement various common splitting operations, and one of them will</span> <a name="line-92"></a><span class='hs-comment'>-- probably do the job 90\% of the time. For example:</span> <a name="line-93"></a><span class='hs-comment'>--</span> <a name="line-94"></a><span class='hs-comment'>-- > > splitOn "x" "axbxc"</span> <a name="line-95"></a><span class='hs-comment'>-- > ["a","b","c"]</span> <a name="line-96"></a><span class='hs-comment'>-- > > splitOn "x" "axbxcx"</span> <a name="line-97"></a><span class='hs-comment'>-- > ["a","b","c",""]</span> <a name="line-98"></a><span class='hs-comment'>-- > > endBy ";" "foo;bar;baz;"</span> <a name="line-99"></a><span class='hs-comment'>-- > ["foo","bar","baz"]</span> <a name="line-100"></a><span class='hs-comment'>-- > > splitWhen (<0) [1,3,-4,5,7,-9,0,2]</span> <a name="line-101"></a><span class='hs-comment'>-- > [[1,3],[5,7],[0,2]]</span> <a name="line-102"></a><span class='hs-comment'>-- > > splitOneOf ";.," "foo,bar;baz.glurk"</span> <a name="line-103"></a><span class='hs-comment'>-- > ["foo","bar","baz","glurk"]</span> <a name="line-104"></a><span class='hs-comment'>-- > > splitEvery 3 ['a'..'z']</span> <a name="line-105"></a><span class='hs-comment'>-- > ["abc","def","ghi","jkl","mno","pqr","stu","vwx","yz"]</span> <a name="line-106"></a><span class='hs-comment'>--</span> <a name="line-107"></a><span class='hs-comment'>-- If you want more flexibility, however, you can use the combinator</span> <a name="line-108"></a><span class='hs-comment'>-- library in terms of which these functions are defined. For more</span> <a name="line-109"></a><span class='hs-comment'>-- information, skip to the section labeled \"Splitting Combinators\".</span> <a name="line-110"></a><span class='hs-comment'>--</span> <a name="line-111"></a><span class='hs-comment'>-- Note that the goal of this library is to be flexible yet simple.</span> <a name="line-112"></a><span class='hs-comment'>-- It does not implement any particularly sophisticated list-splitting</span> <a name="line-113"></a><span class='hs-comment'>-- methods, nor is it tuned for speed. If you find yourself wanting</span> <a name="line-114"></a><span class='hs-comment'>-- something more complicated or optimized, it probably means you</span> <a name="line-115"></a><span class='hs-comment'>-- should use a real parsing or regular expression library.</span> <a name="line-116"></a> <a name="line-117"></a><span class='hs-comment'>-- $conv</span> <a name="line-118"></a><span class='hs-comment'>-- These functions implement some common splitting strategies. Note</span> <a name="line-119"></a><span class='hs-comment'>-- that all of the functions in this section drop delimiters from the</span> <a name="line-120"></a><span class='hs-comment'>-- final output, since that is a more common use case even though it</span> <a name="line-121"></a><span class='hs-comment'>-- is not the default.</span> <a name="line-122"></a> <a name="line-123"></a><span class='hs-comment'>-- $other</span> <a name="line-124"></a><span class='hs-comment'>-- Other useful splitting methods which are not implemented using the</span> <a name="line-125"></a><span class='hs-comment'>-- combinator framework.</span> <a name="line-126"></a> <a name="line-127"></a><span class='hs-comment'>-- $comb</span> <a name="line-128"></a><span class='hs-comment'>-- The core of the library is the 'Splitter' type, which represents a</span> <a name="line-129"></a><span class='hs-comment'>-- particular list-splitting strategy. All of the combinators revolve</span> <a name="line-130"></a><span class='hs-comment'>-- around constructing or transforming 'Splitter' objects; once a</span> <a name="line-131"></a><span class='hs-comment'>-- suitable 'Splitter' has been created, it can be run with the</span> <a name="line-132"></a><span class='hs-comment'>-- 'split' function. For example:</span> <a name="line-133"></a><span class='hs-comment'>--</span> <a name="line-134"></a><span class='hs-comment'>-- > > split (dropBlanks . condense $ whenElt (<0)) [1,2,4,-5,-6,4,9,-19,-30]</span> <a name="line-135"></a><span class='hs-comment'>-- > [[1,2,4],[-5,-6],[4,9],[-19,-30]]</span> <a name="line-136"></a> <a name="line-137"></a><span class='hs-comment'>-- $basic</span> <a name="line-138"></a><span class='hs-comment'>-- All these basic strategies have the same parameters as the</span> <a name="line-139"></a><span class='hs-comment'>-- 'defaultSplitter' except for the delimiter.</span> <a name="line-140"></a> <a name="line-141"></a><span class='hs-comment'>-- $transform</span> <a name="line-142"></a><span class='hs-comment'>-- Functions for altering splitting strategy parameters.</span> <a name="line-143"></a> <a name="line-144"></a><span class='hs-comment'>-- $derived</span> <a name="line-145"></a><span class='hs-comment'>-- Combinators which can be defined in terms of other combinators, but</span> <a name="line-146"></a><span class='hs-comment'>-- are provided for convenience.</span> </pre></body> </html>
