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<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.Version</span>
<a name="line-4"></a><span class='hs-comment'>-- Copyright : (c) The University of Glasgow 2004</span>
<a name="line-5"></a><span class='hs-comment'>-- License : BSD-style (see the file libraries/base/LICENSE)</span>
<a name="line-6"></a><span class='hs-comment'>-- </span>
<a name="line-7"></a><span class='hs-comment'>-- Maintainer : libraries@haskell.org</span>
<a name="line-8"></a><span class='hs-comment'>-- Stability : experimental</span>
<a name="line-9"></a><span class='hs-comment'>-- Portability : non-portable (local universal quantification in ReadP)</span>
<a name="line-10"></a><span class='hs-comment'>--</span>
<a name="line-11"></a><span class='hs-comment'>-- A general library for representation and manipulation of versions.</span>
<a name="line-12"></a><span class='hs-comment'>-- </span>
<a name="line-13"></a><span class='hs-comment'>-- Versioning schemes are many and varied, so the version</span>
<a name="line-14"></a><span class='hs-comment'>-- representation provided by this library is intended to be a</span>
<a name="line-15"></a><span class='hs-comment'>-- compromise between complete generality, where almost no common</span>
<a name="line-16"></a><span class='hs-comment'>-- functionality could reasonably be provided, and fixing a particular</span>
<a name="line-17"></a><span class='hs-comment'>-- versioning scheme, which would probably be too restrictive.</span>
<a name="line-18"></a><span class='hs-comment'>-- </span>
<a name="line-19"></a><span class='hs-comment'>-- So the approach taken here is to provide a representation which</span>
<a name="line-20"></a><span class='hs-comment'>-- subsumes many of the versioning schemes commonly in use, and we</span>
<a name="line-21"></a><span class='hs-comment'>-- provide implementations of 'Eq', 'Ord' and conversion to\/from 'String'</span>
<a name="line-22"></a><span class='hs-comment'>-- which will be appropriate for some applications, but not all.</span>
<a name="line-23"></a><span class='hs-comment'>--</span>
<a name="line-24"></a><span class='hs-comment'>-----------------------------------------------------------------------------</span>
<a name="line-25"></a>
<a name="line-26"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Version</span> <span class='hs-layout'>(</span>
<a name="line-27"></a> <span class='hs-comment'>-- * The @Version@ type</span>
<a name="line-28"></a> <span class='hs-conid'>Version</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span>
<a name="line-29"></a> <span class='hs-comment'>-- * A concrete representation of @Version@</span>
<a name="line-30"></a> <span class='hs-varid'>showVersion</span><span class='hs-layout'>,</span> <span class='hs-varid'>parseVersion</span><span class='hs-layout'>,</span>
<a name="line-31"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-32"></a>
<a name="line-33"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Prelude</span> <span class='hs-comment'>-- necessary to get dependencies right</span>
<a name="line-34"></a>
<a name="line-35"></a><span class='hs-comment'>-- These #ifdefs are necessary because this code might be compiled as</span>
<a name="line-36"></a><span class='hs-comment'>-- part of ghc/lib/compat, and hence might be compiled by an older version</span>
<a name="line-37"></a><span class='hs-comment'>-- of GHC. In which case, we might need to pick up ReadP from </span>
<a name="line-38"></a><span class='hs-comment'>-- Distribution.Compat.ReadP, because the version in </span>
<a name="line-39"></a><span class='hs-comment'>-- Text.ParserCombinators.ReadP doesn't have all the combinators we need.</span>
<a name="line-40"></a><span class='hs-cpp'>#if __GLASGOW_HASKELL__ || __HUGS__ || __NHC__</span>
<a name="line-41"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Text</span><span class='hs-varop'>.</span><span class='hs-conid'>ParserCombinators</span><span class='hs-varop'>.</span><span class='hs-conid'>ReadP</span>
<a name="line-42"></a><span class='hs-cpp'>#else</span>
<a name="line-43"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Distribution</span><span class='hs-varop'>.</span><span class='hs-conid'>Compat</span><span class='hs-varop'>.</span><span class='hs-conid'>ReadP</span>
<a name="line-44"></a><span class='hs-cpp'>#endif</span>
<a name="line-45"></a>
<a name="line-46"></a><span class='hs-cpp'>#if !__GLASGOW_HASKELL__</span>
<a name="line-47"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Typeable</span> <span class='hs-layout'>(</span> <span class='hs-conid'>Typeable</span><span class='hs-layout'>,</span> <span class='hs-conid'>TyCon</span><span class='hs-layout'>,</span> <span class='hs-varid'>mkTyCon</span><span class='hs-layout'>,</span> <span class='hs-varid'>mkTyConApp</span> <span class='hs-layout'>)</span>
<a name="line-48"></a><span class='hs-cpp'>#else</span>
<a name="line-49"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Typeable</span> <span class='hs-layout'>(</span> <span class='hs-conid'>Typeable</span> <span class='hs-layout'>)</span>
<a name="line-50"></a><span class='hs-cpp'>#endif</span>
<a name="line-51"></a>
<a name="line-52"></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-layout'>(</span> <span class='hs-varid'>intersperse</span><span class='hs-layout'>,</span> <span class='hs-varid'>sort</span> <span class='hs-layout'>)</span>
<a name="line-53"></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-54"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Char</span> <span class='hs-layout'>(</span> <span class='hs-varid'>isDigit</span><span class='hs-layout'>,</span> <span class='hs-varid'>isAlphaNum</span> <span class='hs-layout'>)</span>
<a name="line-55"></a>
<a name="line-56"></a><a name="Version"></a><span class='hs-comment'>{- |
<a name="line-57"></a>A 'Version' represents the version of a software entity.
<a name="line-58"></a>
<a name="line-59"></a>An instance of 'Eq' is provided, which implements exact equality
<a name="line-60"></a>modulo reordering of the tags in the 'versionTags' field.
<a name="line-61"></a>
<a name="line-62"></a>An instance of 'Ord' is also provided, which gives lexicographic
<a name="line-63"></a>ordering on the 'versionBranch' fields (i.e. 2.1 > 2.0, 1.2.3 > 1.2.2,
<a name="line-64"></a>etc.). This is expected to be sufficient for many uses, but note that
<a name="line-65"></a>you may need to use a more specific ordering for your versioning
<a name="line-66"></a>scheme. For example, some versioning schemes may include pre-releases
<a name="line-67"></a>which have tags @\"pre1\"@, @\"pre2\"@, and so on, and these would need to
<a name="line-68"></a>be taken into account when determining ordering. In some cases, date
<a name="line-69"></a>ordering may be more appropriate, so the application would have to
<a name="line-70"></a>look for @date@ tags in the 'versionTags' field and compare those.
<a name="line-71"></a>The bottom line is, don't always assume that 'compare' and other 'Ord'
<a name="line-72"></a>operations are the right thing for every 'Version'.
<a name="line-73"></a>
<a name="line-74"></a>Similarly, concrete representations of versions may differ. One
<a name="line-75"></a>possible concrete representation is provided (see 'showVersion' and
<a name="line-76"></a>'parseVersion'), but depending on the application a different concrete
<a name="line-77"></a>representation may be more appropriate.
<a name="line-78"></a>-}</span>
<a name="line-79"></a><a name="Version"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Version</span> <span class='hs-keyglyph'>=</span>
<a name="line-80"></a> <span class='hs-conid'>Version</span> <span class='hs-layout'>{</span> <span class='hs-varid'>versionBranch</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Int</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>,</span>
<a name="line-81"></a> <span class='hs-comment'>-- ^ The numeric branch for this version. This reflects the</span>
<a name="line-82"></a> <span class='hs-comment'>-- fact that most software versions are tree-structured; there</span>
<a name="line-83"></a> <span class='hs-comment'>-- is a main trunk which is tagged with versions at various</span>
<a name="line-84"></a> <span class='hs-comment'>-- points (1,2,3...), and the first branch off the trunk after</span>
<a name="line-85"></a> <span class='hs-comment'>-- version 3 is 3.1, the second branch off the trunk after</span>
<a name="line-86"></a> <span class='hs-comment'>-- version 3 is 3.2, and so on. The tree can be branched</span>
<a name="line-87"></a> <span class='hs-comment'>-- arbitrarily, just by adding more digits.</span>
<a name="line-88"></a> <span class='hs-comment'>-- </span>
<a name="line-89"></a> <span class='hs-comment'>-- We represent the branch as a list of 'Int', so</span>
<a name="line-90"></a> <span class='hs-comment'>-- version 3.2.1 becomes [3,2,1]. Lexicographic ordering</span>
<a name="line-91"></a> <span class='hs-comment'>-- (i.e. the default instance of 'Ord' for @[Int]@) gives</span>
<a name="line-92"></a> <span class='hs-comment'>-- the natural ordering of branches.</span>
<a name="line-93"></a>
<a name="line-94"></a> <span class='hs-varid'>versionTags</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>String</span><span class='hs-keyglyph'>]</span> <span class='hs-comment'>-- really a bag</span>
<a name="line-95"></a> <span class='hs-comment'>-- ^ A version can be tagged with an arbitrary list of strings.</span>
<a name="line-96"></a> <span class='hs-comment'>-- The interpretation of the list of tags is entirely dependent</span>
<a name="line-97"></a> <span class='hs-comment'>-- on the entity that this version applies to.</span>
<a name="line-98"></a> <span class='hs-layout'>}</span>
<a name="line-99"></a> <span class='hs-keyword'>deriving</span> <span class='hs-layout'>(</span><span class='hs-conid'>Read</span><span class='hs-layout'>,</span><span class='hs-conid'>Show</span>
<a name="line-100"></a><span class='hs-cpp'>#if __GLASGOW_HASKELL__</span>
<a name="line-101"></a> <span class='hs-layout'>,</span><span class='hs-conid'>Typeable</span>
<a name="line-102"></a><span class='hs-cpp'>#endif</span>
<a name="line-103"></a> <span class='hs-layout'>)</span>
<a name="line-104"></a>
<a name="line-105"></a><span class='hs-cpp'>#if !__GLASGOW_HASKELL__</span>
<a name="line-106"></a><a name="versionTc"></a><span class='hs-definition'>versionTc</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>TyCon</span>
<a name="line-107"></a><span class='hs-definition'>versionTc</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mkTyCon</span> <span class='hs-str'>"Version"</span>
<a name="line-108"></a>
<a name="line-109"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Typeable</span> <span class='hs-conid'>Version</span> <span class='hs-keyword'>where</span>
<a name="line-110"></a> <span class='hs-varid'>typeOf</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mkTyConApp</span> <span class='hs-varid'>versionTc</span> <span class='hs-conid'>[]</span>
<a name="line-111"></a><span class='hs-cpp'>#endif</span>
<a name="line-112"></a>
<a name="line-113"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Eq</span> <span class='hs-conid'>Version</span> <span class='hs-keyword'>where</span>
<a name="line-114"></a> <span class='hs-varid'>v1</span> <span class='hs-varop'>==</span> <span class='hs-varid'>v2</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>versionBranch</span> <span class='hs-varid'>v1</span> <span class='hs-varop'>==</span> <span class='hs-varid'>versionBranch</span> <span class='hs-varid'>v2</span>
<a name="line-115"></a> <span class='hs-varop'>&&</span> <span class='hs-varid'>sort</span> <span class='hs-layout'>(</span><span class='hs-varid'>versionTags</span> <span class='hs-varid'>v1</span><span class='hs-layout'>)</span> <span class='hs-varop'>==</span> <span class='hs-varid'>sort</span> <span class='hs-layout'>(</span><span class='hs-varid'>versionTags</span> <span class='hs-varid'>v2</span><span class='hs-layout'>)</span>
<a name="line-116"></a> <span class='hs-comment'>-- tags may be in any order</span>
<a name="line-117"></a>
<a name="line-118"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Ord</span> <span class='hs-conid'>Version</span> <span class='hs-keyword'>where</span>
<a name="line-119"></a> <span class='hs-varid'>v1</span> <span class='hs-varop'>`compare`</span> <span class='hs-varid'>v2</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>versionBranch</span> <span class='hs-varid'>v1</span> <span class='hs-varop'>`compare`</span> <span class='hs-varid'>versionBranch</span> <span class='hs-varid'>v2</span>
<a name="line-120"></a>
<a name="line-121"></a><span class='hs-comment'>-- -----------------------------------------------------------------------------</span>
<a name="line-122"></a><span class='hs-comment'>-- A concrete representation of 'Version'</span>
<a name="line-123"></a>
<a name="line-124"></a><a name="showVersion"></a><span class='hs-comment'>-- | Provides one possible concrete representation for 'Version'. For</span>
<a name="line-125"></a><span class='hs-comment'>-- a version with 'versionBranch' @= [1,2,3]@ and 'versionTags' </span>
<a name="line-126"></a><span class='hs-comment'>-- @= [\"tag1\",\"tag2\"]@, the output will be @1.2.3-tag1-tag2@.</span>
<a name="line-127"></a><span class='hs-comment'>--</span>
<a name="line-128"></a><span class='hs-definition'>showVersion</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Version</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span>
<a name="line-129"></a><span class='hs-definition'>showVersion</span> <span class='hs-layout'>(</span><span class='hs-conid'>Version</span> <span class='hs-varid'>branch</span> <span class='hs-varid'>tags</span><span class='hs-layout'>)</span>
<a name="line-130"></a> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>concat</span> <span class='hs-layout'>(</span><span class='hs-varid'>intersperse</span> <span class='hs-str'>"."</span> <span class='hs-layout'>(</span><span class='hs-varid'>map</span> <span class='hs-varid'>show</span> <span class='hs-varid'>branch</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-varop'>++</span>
<a name="line-131"></a> <span class='hs-varid'>concatMap</span> <span class='hs-layout'>(</span><span class='hs-chr'>'-'</span><span class='hs-conop'>:</span><span class='hs-layout'>)</span> <span class='hs-varid'>tags</span>
<a name="line-132"></a>
<a name="line-133"></a><span class='hs-comment'>-- | A parser for versions in the format produced by 'showVersion'.</span>
<a name="line-134"></a><span class='hs-comment'>--</span>
<a name="line-135"></a><span class='hs-cpp'>#if __GLASGOW_HASKELL__ || __HUGS__</span>
<a name="line-136"></a><a name="parseVersion"></a><span class='hs-definition'>parseVersion</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-conid'>Version</span>
<a name="line-137"></a><span class='hs-cpp'>#elif __NHC__</span>
<a name="line-138"></a><span class='hs-definition'>parseVersion</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadPN</span> <span class='hs-varid'>r</span> <span class='hs-conid'>Version</span>
<a name="line-139"></a><span class='hs-cpp'>#else</span>
<a name="line-140"></a><span class='hs-definition'>parseVersion</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>Version</span>
<a name="line-141"></a><span class='hs-cpp'>#endif</span>
<a name="line-142"></a><span class='hs-definition'>parseVersion</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>branch</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>sepBy1</span> <span class='hs-layout'>(</span><span class='hs-varid'>liftM</span> <span class='hs-varid'>read</span> <span class='hs-varop'>$</span> <span class='hs-varid'>munch1</span> <span class='hs-varid'>isDigit</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>char</span> <span class='hs-chr'>'.'</span><span class='hs-layout'>)</span>
<a name="line-143"></a> <span class='hs-varid'>tags</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>many</span> <span class='hs-layout'>(</span><span class='hs-varid'>char</span> <span class='hs-chr'>'-'</span> <span class='hs-varop'>>></span> <span class='hs-varid'>munch1</span> <span class='hs-varid'>isAlphaNum</span><span class='hs-layout'>)</span>
<a name="line-144"></a> <span class='hs-varid'>return</span> <span class='hs-conid'>Version</span><span class='hs-layout'>{</span><span class='hs-varid'>versionBranch</span><span class='hs-keyglyph'>=</span><span class='hs-varid'>branch</span><span class='hs-layout'>,</span> <span class='hs-varid'>versionTags</span><span class='hs-keyglyph'>=</span><span class='hs-varid'>tags</span><span class='hs-layout'>}</span>
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