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<pre><a name="line-1"></a><span class='hs-comment'>-- To make GHC stop warning about the Prelude</span>
<a name="line-2"></a><span class='hs-comment'>{-# OPTIONS_GHC -Wall -fwarn-tabs -fno-warn-unused-imports #-}</span>
<a name="line-3"></a><span class='hs-comment'>{-# LANGUAGE NoImplicitPrelude #-}</span>
<a name="line-4"></a><span class='hs-comment'>----------------------------------------------------------------</span>
<a name="line-5"></a><span class='hs-comment'>-- ~ 2011.02.12</span>
<a name="line-6"></a><span class='hs-comment'>-- |</span>
<a name="line-7"></a><span class='hs-comment'>-- Module : Data.Trie</span>
<a name="line-8"></a><span class='hs-comment'>-- Copyright : Copyright (c) 2008--2011 wren ng thornton</span>
<a name="line-9"></a><span class='hs-comment'>-- License : BSD3</span>
<a name="line-10"></a><span class='hs-comment'>-- Maintainer : wren@community.haskell.org</span>
<a name="line-11"></a><span class='hs-comment'>-- Stability : experimental</span>
<a name="line-12"></a><span class='hs-comment'>-- Portability : portable</span>
<a name="line-13"></a><span class='hs-comment'>--</span>
<a name="line-14"></a><span class='hs-comment'>-- An efficient implementation of finite maps from strings to values.</span>
<a name="line-15"></a><span class='hs-comment'>-- The implementation is based on /big-endian patricia trees/, like</span>
<a name="line-16"></a><span class='hs-comment'>-- "Data.IntMap". We first trie on the elements of "Data.ByteString"</span>
<a name="line-17"></a><span class='hs-comment'>-- and then trie on the big-endian bit representation of those</span>
<a name="line-18"></a><span class='hs-comment'>-- elements. For further details on the latter, see</span>
<a name="line-19"></a><span class='hs-comment'>--</span>
<a name="line-20"></a><span class='hs-comment'>-- * Chris Okasaki and Andy Gill, \"/Fast Mergeable Integer Maps/\",</span>
<a name="line-21"></a><span class='hs-comment'>-- Workshop on ML, September 1998, pages 77-86,</span>
<a name="line-22"></a><span class='hs-comment'>-- <<a href="http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.37.5452">http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.37.5452</a>></span>
<a name="line-23"></a><span class='hs-comment'>--</span>
<a name="line-24"></a><span class='hs-comment'>-- * D.R. Morrison, \"/PATRICIA -- Practical Algorithm To Retrieve/</span>
<a name="line-25"></a><span class='hs-comment'>-- /Information Coded In Alphanumeric/\", Journal of the ACM, 15(4),</span>
<a name="line-26"></a><span class='hs-comment'>-- October 1968, pages 514-534.</span>
<a name="line-27"></a><span class='hs-comment'>--</span>
<a name="line-28"></a><span class='hs-comment'>-- This module aims to provide an austere interface, while being</span>
<a name="line-29"></a><span class='hs-comment'>-- detailed enough for most users. For an extended interface with</span>
<a name="line-30"></a><span class='hs-comment'>-- many additional functions, see "Data.Trie.Convenience". For</span>
<a name="line-31"></a><span class='hs-comment'>-- functions that give more detailed (potentially abstraction-breaking)</span>
<a name="line-32"></a><span class='hs-comment'>-- access to the data strucuture, or for experimental functions</span>
<a name="line-33"></a><span class='hs-comment'>-- which aren't quite ready for the public API, see "Data.Trie.Internal".</span>
<a name="line-34"></a><span class='hs-comment'>----------------------------------------------------------------</span>
<a name="line-35"></a>
<a name="line-36"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Trie</span>
<a name="line-37"></a> <span class='hs-layout'>(</span>
<a name="line-38"></a> <span class='hs-comment'>-- * Data type</span>
<a name="line-39"></a> <span class='hs-conid'>Trie</span><span class='hs-conid'>()</span>
<a name="line-40"></a>
<a name="line-41"></a> <span class='hs-comment'>-- * Basic functions</span>
<a name="line-42"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>empty</span><span class='hs-layout'>,</span> <span class='hs-varid'>null</span><span class='hs-layout'>,</span> <span class='hs-varid'>singleton</span><span class='hs-layout'>,</span> <span class='hs-varid'>size</span>
<a name="line-43"></a>
<a name="line-44"></a> <span class='hs-comment'>-- * Conversion functions</span>
<a name="line-45"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>fromList</span><span class='hs-layout'>,</span> <span class='hs-varid'>toListBy</span><span class='hs-layout'>,</span> <span class='hs-varid'>toList</span><span class='hs-layout'>,</span> <span class='hs-varid'>keys</span><span class='hs-layout'>,</span> <span class='hs-varid'>elems</span>
<a name="line-46"></a>
<a name="line-47"></a> <span class='hs-comment'>-- * Query functions</span>
<a name="line-48"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>lookupBy</span><span class='hs-layout'>,</span> <span class='hs-varid'>lookup</span><span class='hs-layout'>,</span> <span class='hs-varid'>member</span><span class='hs-layout'>,</span> <span class='hs-varid'>submap</span>
<a name="line-49"></a>
<a name="line-50"></a> <span class='hs-comment'>-- * Single-value modification</span>
<a name="line-51"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>alterBy</span><span class='hs-layout'>,</span> <span class='hs-varid'>insert</span><span class='hs-layout'>,</span> <span class='hs-varid'>adjust</span><span class='hs-layout'>,</span> <span class='hs-varid'>delete</span>
<a name="line-52"></a>
<a name="line-53"></a> <span class='hs-comment'>-- * Combining tries</span>
<a name="line-54"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>mergeBy</span><span class='hs-layout'>,</span> <span class='hs-varid'>unionL</span><span class='hs-layout'>,</span> <span class='hs-varid'>unionR</span>
<a name="line-55"></a>
<a name="line-56"></a> <span class='hs-comment'>-- * Mapping functions</span>
<a name="line-57"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>mapBy</span><span class='hs-layout'>,</span> <span class='hs-varid'>filterMap</span>
<a name="line-58"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-59"></a>
<a name="line-60"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Prelude</span> <span class='hs-varid'>hiding</span> <span class='hs-layout'>(</span><span class='hs-varid'>null</span><span class='hs-layout'>,</span> <span class='hs-varid'>lookup</span><span class='hs-layout'>)</span>
<a name="line-61"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Prelude</span> <span class='hs-layout'>(</span><span class='hs-varid'>null</span><span class='hs-layout'>,</span> <span class='hs-varid'>lookup</span><span class='hs-layout'>)</span>
<a name="line-62"></a>
<a name="line-63"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Trie</span><span class='hs-varop'>.</span><span class='hs-conid'>Internal</span>
<a name="line-64"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Trie</span><span class='hs-varop'>.</span><span class='hs-conid'>Errors</span> <span class='hs-layout'>(</span><span class='hs-varid'>impossible</span><span class='hs-layout'>)</span>
<a name="line-65"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span> <span class='hs-layout'>(</span><span class='hs-conid'>ByteString</span><span class='hs-layout'>)</span>
<a name="line-66"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span><span class='hs-varid'>isJust</span><span class='hs-layout'>)</span>
<a name="line-67"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span> <span class='hs-layout'>(</span><span class='hs-varid'>liftM</span><span class='hs-layout'>)</span>
<a name="line-68"></a><span class='hs-comment'>----------------------------------------------------------------</span>
<a name="line-69"></a><span class='hs-comment'>----------------------------------------------------------------</span>
<a name="line-70"></a>
<a name="line-71"></a>
<a name="line-72"></a><span class='hs-comment'>{---------------------------------------------------------------
<a name="line-73"></a>-- Conversion functions
<a name="line-74"></a>---------------------------------------------------------------}</span>
<a name="line-75"></a>
<a name="line-76"></a><a name="fromList"></a><span class='hs-comment'>-- | Convert association list into a trie. On key conflict, values</span>
<a name="line-77"></a><span class='hs-comment'>-- earlier in the list shadow later ones.</span>
<a name="line-78"></a><span class='hs-definition'>fromList</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-layout'>(</span><span class='hs-conid'>ByteString</span><span class='hs-layout'>,</span><span class='hs-varid'>a</span><span class='hs-layout'>)</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span>
<a name="line-79"></a><span class='hs-comment'>{-# INLINE fromList #-}</span>
<a name="line-80"></a><span class='hs-definition'>fromList</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>foldr</span> <span class='hs-layout'>(</span><span class='hs-varid'>uncurry</span> <span class='hs-varid'>insert</span><span class='hs-layout'>)</span> <span class='hs-varid'>empty</span>
<a name="line-81"></a>
<a name="line-82"></a><a name="toList"></a><span class='hs-comment'>-- | Convert trie into association list. Keys will be in sorted order.</span>
<a name="line-83"></a><span class='hs-definition'>toList</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-layout'>(</span><span class='hs-conid'>ByteString</span><span class='hs-layout'>,</span><span class='hs-varid'>a</span><span class='hs-layout'>)</span><span class='hs-keyglyph'>]</span>
<a name="line-84"></a><span class='hs-comment'>{-# INLINE toList #-}</span>
<a name="line-85"></a><span class='hs-definition'>toList</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>toListBy</span> <span class='hs-conid'>(,)</span>
<a name="line-86"></a>
<a name="line-87"></a><span class='hs-comment'>-- FIX? should 'keys' and 'elems' move to Data.Trie.Convenience instead?</span>
<a name="line-88"></a>
<a name="line-89"></a><a name="keys"></a><span class='hs-comment'>-- | Return all keys in the trie, in sorted order.</span>
<a name="line-90"></a><span class='hs-definition'>keys</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>ByteString</span><span class='hs-keyglyph'>]</span>
<a name="line-91"></a><span class='hs-comment'>{-# INLINE keys #-}</span>
<a name="line-92"></a><span class='hs-definition'>keys</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>toListBy</span> <span class='hs-varid'>const</span>
<a name="line-93"></a>
<a name="line-94"></a><a name="elems"></a><span class='hs-comment'>-- | Return all values in the trie, in sorted order according to the keys.</span>
<a name="line-95"></a><span class='hs-definition'>elems</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-96"></a><span class='hs-comment'>{-# INLINE elems #-}</span>
<a name="line-97"></a><span class='hs-definition'>elems</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>toListBy</span> <span class='hs-layout'>(</span><span class='hs-varid'>flip</span> <span class='hs-varid'>const</span><span class='hs-layout'>)</span>
<a name="line-98"></a>
<a name="line-99"></a>
<a name="line-100"></a><span class='hs-comment'>{---------------------------------------------------------------
<a name="line-101"></a>-- Query functions (just recurse)
<a name="line-102"></a>---------------------------------------------------------------}</span>
<a name="line-103"></a>
<a name="line-104"></a><a name="lookupBy"></a><span class='hs-comment'>-- | Generic function to find a value (if it exists) and the subtrie</span>
<a name="line-105"></a><span class='hs-comment'>-- rooted at the prefix.</span>
<a name="line-106"></a><span class='hs-definition'>lookupBy</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Maybe</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>b</span>
<a name="line-107"></a><span class='hs-comment'>{-# INLINE lookupBy #-}</span>
<a name="line-108"></a><span class='hs-definition'>lookupBy</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>lookupBy_</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-conid'>Nothing</span> <span class='hs-varid'>empty</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-conid'>Nothing</span><span class='hs-layout'>)</span>
<a name="line-109"></a>
<a name="line-110"></a><a name="lookup"></a><span class='hs-comment'>-- | Return the value associated with a query string if it exists.</span>
<a name="line-111"></a><span class='hs-definition'>lookup</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-varid'>a</span>
<a name="line-112"></a><span class='hs-comment'>{-# INLINE lookup #-}</span>
<a name="line-113"></a><span class='hs-definition'>lookup</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>lookupBy_</span> <span class='hs-varid'>const</span> <span class='hs-conid'>Nothing</span> <span class='hs-layout'>(</span><span class='hs-varid'>const</span> <span class='hs-conid'>Nothing</span><span class='hs-layout'>)</span>
<a name="line-114"></a>
<a name="line-115"></a><a name="member"></a><span class='hs-comment'>-- TODO? move to "Data.Trie.Conventience"?</span>
<a name="line-116"></a><span class='hs-comment'>-- | Does a string have a value in the trie?</span>
<a name="line-117"></a><span class='hs-definition'>member</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span>
<a name="line-118"></a><span class='hs-comment'>{-# INLINE member #-}</span>
<a name="line-119"></a><span class='hs-definition'>member</span> <span class='hs-varid'>q</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>isJust</span> <span class='hs-varop'>.</span> <span class='hs-varid'>lookup</span> <span class='hs-varid'>q</span>
<a name="line-120"></a>
<a name="line-121"></a>
<a name="line-122"></a><span class='hs-comment'>{---------------------------------------------------------------
<a name="line-123"></a>-- Single-value modification functions (recurse and clone spine)
<a name="line-124"></a>---------------------------------------------------------------}</span>
<a name="line-125"></a>
<a name="line-126"></a><a name="insert"></a><span class='hs-comment'>-- | Insert a new key. If the key is already present, overrides the</span>
<a name="line-127"></a><span class='hs-comment'>-- old value</span>
<a name="line-128"></a><span class='hs-definition'>insert</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span>
<a name="line-129"></a><span class='hs-comment'>{-# INLINE insert #-}</span>
<a name="line-130"></a><span class='hs-definition'>insert</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>alterBy</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-keyword'>_</span> <span class='hs-varid'>x</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Just</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span>
<a name="line-131"></a>
<a name="line-132"></a><a name="adjust"></a><span class='hs-comment'>-- | Apply a function to the value at a key.</span>
<a name="line-133"></a><span class='hs-definition'>adjust</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span>
<a name="line-134"></a><span class='hs-comment'>{-# INLINE adjust #-}</span>
<a name="line-135"></a><span class='hs-definition'>adjust</span> <span class='hs-varid'>f</span> <span class='hs-varid'>q</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>adjustBy</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-keyword'>_</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span> <span class='hs-varid'>q</span> <span class='hs-layout'>(</span><span class='hs-varid'>impossible</span> <span class='hs-str'>"adjust"</span><span class='hs-layout'>)</span>
<a name="line-136"></a><span class='hs-comment'>-- TODO: benchmark vs the definition with alterBy/liftM</span>
<a name="line-137"></a>
<a name="line-138"></a><a name="delete"></a><span class='hs-comment'>-- | Remove the value stored at a key.</span>
<a name="line-139"></a><span class='hs-definition'>delete</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ByteString</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span>
<a name="line-140"></a><span class='hs-comment'>{-# INLINE delete #-}</span>
<a name="line-141"></a><span class='hs-definition'>delete</span> <span class='hs-varid'>q</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>alterBy</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-keyword'>_</span> <span class='hs-keyword'>_</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Nothing</span><span class='hs-layout'>)</span> <span class='hs-varid'>q</span> <span class='hs-layout'>(</span><span class='hs-varid'>impossible</span> <span class='hs-str'>"delete"</span><span class='hs-layout'>)</span>
<a name="line-142"></a>
<a name="line-143"></a>
<a name="line-144"></a><span class='hs-comment'>{---------------------------------------------------------------
<a name="line-145"></a>-- Trie-combining functions
<a name="line-146"></a>---------------------------------------------------------------}</span>
<a name="line-147"></a>
<a name="line-148"></a><a name="unionL"></a><span class='hs-comment'>-- | Combine two tries, resolving conflicts by choosing the value</span>
<a name="line-149"></a><span class='hs-comment'>-- from the left trie.</span>
<a name="line-150"></a><span class='hs-definition'>unionL</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span>
<a name="line-151"></a><span class='hs-comment'>{-# INLINE unionL #-}</span>
<a name="line-152"></a><span class='hs-definition'>unionL</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mergeBy</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>x</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Just</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span>
<a name="line-153"></a>
<a name="line-154"></a><a name="unionR"></a><span class='hs-comment'>-- | Combine two tries, resolving conflicts by choosing the value</span>
<a name="line-155"></a><span class='hs-comment'>-- from the right trie.</span>
<a name="line-156"></a><span class='hs-definition'>unionR</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Trie</span> <span class='hs-varid'>a</span>
<a name="line-157"></a><span class='hs-comment'>{-# INLINE unionR #-}</span>
<a name="line-158"></a><span class='hs-definition'>unionR</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mergeBy</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-keyword'>_</span> <span class='hs-varid'>y</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Just</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-159"></a>
<a name="line-160"></a><span class='hs-comment'>----------------------------------------------------------------</span>
<a name="line-161"></a><span class='hs-comment'>----------------------------------------------------------- fin.</span>
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