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<pre><a name="line-1"></a><span class='hs-comment'>{- arch-tag: Time utilities main file
<a name="line-2"></a>Copyright (C) 2004-2005 John Goerzen <jgoerzen@complete.org>
<a name="line-3"></a>
<a name="line-4"></a>This program is free software; you can redistribute it and/or modify
<a name="line-5"></a>it under the terms of the GNU General Public License as published by
<a name="line-6"></a>the Free Software Foundation; either version 2 of the License, or
<a name="line-7"></a>(at your option) any later version.
<a name="line-8"></a>
<a name="line-9"></a>This program is distributed in the hope that it will be useful,
<a name="line-10"></a>but WITHOUT ANY WARRANTY; without even the implied warranty of
<a name="line-11"></a>MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
<a name="line-12"></a>GNU General Public License for more details.
<a name="line-13"></a>
<a name="line-14"></a>You should have received a copy of the GNU General Public License
<a name="line-15"></a>along with this program; if not, write to the Free Software
<a name="line-16"></a>Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
<a name="line-17"></a>-}</span>
<a name="line-18"></a>
<a name="line-19"></a><span class='hs-comment'>{- |
<a name="line-20"></a> Module : System.Time.Utils
<a name="line-21"></a> Copyright : Copyright (C) 2004-2005 John Goerzen
<a name="line-22"></a> License : GNU GPL, version 2 or above
<a name="line-23"></a>
<a name="line-24"></a> Maintainer : John Goerzen <jgoerzen@complete.org>
<a name="line-25"></a> Stability : provisional
<a name="line-26"></a> Portability: portable
<a name="line-27"></a>
<a name="line-28"></a>This module provides various Haskell utilities for dealing with times and
<a name="line-29"></a>dates.
<a name="line-30"></a>
<a name="line-31"></a>Written by John Goerzen, jgoerzen\@complete.org
<a name="line-32"></a>-}</span>
<a name="line-33"></a>
<a name="line-34"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Time</span><span class='hs-varop'>.</span><span class='hs-conid'>Utils</span><span class='hs-layout'>(</span>
<a name="line-35"></a> <span class='hs-varid'>timelocal</span><span class='hs-layout'>,</span>
<a name="line-36"></a> <span class='hs-varid'>timegm</span><span class='hs-layout'>,</span>
<a name="line-37"></a> <span class='hs-varid'>timeDiffToSecs</span><span class='hs-layout'>,</span>
<a name="line-38"></a> <span class='hs-varid'>epoch</span><span class='hs-layout'>,</span>
<a name="line-39"></a> <span class='hs-varid'>epochToClockTime</span><span class='hs-layout'>,</span>
<a name="line-40"></a> <span class='hs-varid'>clockTimeToEpoch</span><span class='hs-layout'>,</span>
<a name="line-41"></a> <span class='hs-varid'>renderSecs</span><span class='hs-layout'>,</span> <span class='hs-varid'>renderTD</span>
<a name="line-42"></a> <span class='hs-layout'>)</span>
<a name="line-43"></a><span class='hs-keyword'>where</span>
<a name="line-44"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Time</span>
<a name="line-45"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Ratio</span>
<a name="line-46"></a>
<a name="line-47"></a><a name="epoch"></a><span class='hs-comment'>{- | January 1, 1970, midnight, UTC, represented as a CalendarTime. -}</span>
<a name="line-48"></a><span class='hs-definition'>epoch</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>CalendarTime</span>
<a name="line-49"></a><span class='hs-definition'>epoch</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>CalendarTime</span> <span class='hs-layout'>{</span> <span class='hs-varid'>ctYear</span> <span class='hs-keyglyph'>=</span> <span class='hs-num'>1970</span><span class='hs-layout'>,</span> <span class='hs-varid'>ctMonth</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>January</span><span class='hs-layout'>,</span>
<a name="line-50"></a> <span class='hs-varid'>ctDay</span> <span class='hs-keyglyph'>=</span> <span class='hs-num'>1</span><span class='hs-layout'>,</span> <span class='hs-varid'>ctHour</span> <span class='hs-keyglyph'>=</span> <span class='hs-num'>0</span><span class='hs-layout'>,</span> <span class='hs-varid'>ctMin</span> <span class='hs-keyglyph'>=</span> <span class='hs-num'>0</span><span class='hs-layout'>,</span> <span class='hs-varid'>ctSec</span> <span class='hs-keyglyph'>=</span> <span class='hs-num'>0</span><span class='hs-layout'>,</span>
<a name="line-51"></a> <span class='hs-varid'>ctPicosec</span> <span class='hs-keyglyph'>=</span> <span class='hs-num'>0</span><span class='hs-layout'>,</span> <span class='hs-varid'>ctWDay</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Thursday</span><span class='hs-layout'>,</span> <span class='hs-varid'>ctYDay</span> <span class='hs-keyglyph'>=</span> <span class='hs-num'>0</span><span class='hs-layout'>,</span>
<a name="line-52"></a> <span class='hs-varid'>ctTZName</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"UTC"</span><span class='hs-layout'>,</span> <span class='hs-varid'>ctTZ</span> <span class='hs-keyglyph'>=</span> <span class='hs-num'>0</span><span class='hs-layout'>,</span> <span class='hs-varid'>ctIsDST</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>False</span><span class='hs-layout'>}</span>
<a name="line-53"></a>
<a name="line-54"></a><span class='hs-comment'>{- | Converts the specified CalendarTime (see System.Time) to seconds-since-epoch time.
<a name="line-55"></a>
<a name="line-56"></a>This conversion does respect the timezone specified on the input object.
<a name="line-57"></a>If you want a conversion from UTC, specify ctTZ = 0 and ctIsDST = False.
<a name="line-58"></a>
<a name="line-59"></a>When called like that, the behavior is equivolent to the GNU C function
<a name="line-60"></a>timegm(). Unlike the C library, Haskell's CalendarTime supports
<a name="line-61"></a>timezone information, so if such information is specified, it will impact
<a name="line-62"></a>the result.
<a name="line-63"></a>-}</span>
<a name="line-64"></a>
<a name="line-65"></a><a name="timegm"></a><span class='hs-definition'>timegm</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>CalendarTime</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Integer</span>
<a name="line-66"></a><span class='hs-definition'>timegm</span> <span class='hs-varid'>ct</span> <span class='hs-keyglyph'>=</span>
<a name="line-67"></a> <span class='hs-varid'>timeDiffToSecs</span> <span class='hs-layout'>(</span><span class='hs-varid'>diffClockTimes</span> <span class='hs-layout'>(</span><span class='hs-varid'>toClockTime</span> <span class='hs-varid'>ct</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>toClockTime</span> <span class='hs-varid'>epoch</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-68"></a>
<a name="line-69"></a><span class='hs-comment'>{- | Converts the specified CalendarTime (see System.Time) to
<a name="line-70"></a>seconds-since-epoch format.
<a name="line-71"></a>
<a name="line-72"></a>The input CalendarTime is assumed to be the time as given in your local
<a name="line-73"></a>timezone. All timezone and DST fields in the object are ignored.
<a name="line-74"></a>
<a name="line-75"></a>This behavior is equivolent to the timelocal() and mktime() functions that
<a name="line-76"></a>C programmers are accustomed to.
<a name="line-77"></a>
<a name="line-78"></a>Please note that the behavior for this function during the hour immediately
<a name="line-79"></a>before or after a DST switchover may produce a result with a different hour
<a name="line-80"></a>than you expect.
<a name="line-81"></a>-}</span>
<a name="line-82"></a>
<a name="line-83"></a><a name="timelocal"></a><span class='hs-definition'>timelocal</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>CalendarTime</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Integer</span>
<a name="line-84"></a><span class='hs-definition'>timelocal</span> <span class='hs-varid'>ct</span> <span class='hs-keyglyph'>=</span>
<a name="line-85"></a> <span class='hs-keyword'>do</span> <span class='hs-varid'>guessct</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>toCalendarTime</span> <span class='hs-varid'>guesscl</span>
<a name="line-86"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>newct</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>ct</span> <span class='hs-layout'>{</span><span class='hs-varid'>ctTZ</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>ctTZ</span> <span class='hs-varid'>guessct</span><span class='hs-layout'>}</span>
<a name="line-87"></a> <span class='hs-varid'>return</span> <span class='hs-varop'>$</span> <span class='hs-varid'>timegm</span> <span class='hs-varid'>newct</span>
<a name="line-88"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>guesscl</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>toClockTime</span> <span class='hs-varid'>ct</span>
<a name="line-89"></a>
<a name="line-90"></a><a name="timeDiffToSecs"></a><span class='hs-comment'>{- | Converts the given timeDiff to the number of seconds it represents.
<a name="line-91"></a>
<a name="line-92"></a>Uses the same algorithm as normalizeTimeDiff in GHC. -}</span>
<a name="line-93"></a><span class='hs-definition'>timeDiffToSecs</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>TimeDiff</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Integer</span>
<a name="line-94"></a><span class='hs-definition'>timeDiffToSecs</span> <span class='hs-varid'>td</span> <span class='hs-keyglyph'>=</span>
<a name="line-95"></a> <span class='hs-layout'>(</span><span class='hs-varid'>fromIntegral</span> <span class='hs-varop'>$</span> <span class='hs-varid'>tdSec</span> <span class='hs-varid'>td</span><span class='hs-layout'>)</span> <span class='hs-varop'>+</span>
<a name="line-96"></a> <span class='hs-num'>60</span> <span class='hs-varop'>*</span> <span class='hs-layout'>(</span><span class='hs-layout'>(</span><span class='hs-varid'>fromIntegral</span> <span class='hs-varop'>$</span> <span class='hs-varid'>tdMin</span> <span class='hs-varid'>td</span><span class='hs-layout'>)</span> <span class='hs-varop'>+</span>
<a name="line-97"></a> <span class='hs-num'>60</span> <span class='hs-varop'>*</span> <span class='hs-layout'>(</span><span class='hs-layout'>(</span><span class='hs-varid'>fromIntegral</span> <span class='hs-varop'>$</span> <span class='hs-varid'>tdHour</span> <span class='hs-varid'>td</span><span class='hs-layout'>)</span> <span class='hs-varop'>+</span>
<a name="line-98"></a> <span class='hs-num'>24</span> <span class='hs-varop'>*</span> <span class='hs-layout'>(</span><span class='hs-layout'>(</span><span class='hs-varid'>fromIntegral</span> <span class='hs-varop'>$</span> <span class='hs-varid'>tdDay</span> <span class='hs-varid'>td</span><span class='hs-layout'>)</span> <span class='hs-varop'>+</span>
<a name="line-99"></a> <span class='hs-num'>30</span> <span class='hs-varop'>*</span> <span class='hs-layout'>(</span><span class='hs-layout'>(</span><span class='hs-varid'>fromIntegral</span> <span class='hs-varop'>$</span> <span class='hs-varid'>tdMonth</span> <span class='hs-varid'>td</span><span class='hs-layout'>)</span> <span class='hs-varop'>+</span>
<a name="line-100"></a> <span class='hs-num'>365</span> <span class='hs-varop'>*</span> <span class='hs-layout'>(</span><span class='hs-varid'>fromIntegral</span> <span class='hs-varop'>$</span> <span class='hs-varid'>tdYear</span> <span class='hs-varid'>td</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-101"></a>
<a name="line-102"></a><a name="epochToClockTime"></a><span class='hs-comment'>{- | Converts an Epoch time represented with an arbitrary Real to a ClockTime.
<a name="line-103"></a>This input could be a CTime from Foreign.C.Types or an EpochTime from
<a name="line-104"></a>System.Posix.Types. -}</span>
<a name="line-105"></a><span class='hs-definition'>epochToClockTime</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Real</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>ClockTime</span>
<a name="line-106"></a><span class='hs-definition'>epochToClockTime</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span>
<a name="line-107"></a> <span class='hs-conid'>TOD</span> <span class='hs-varid'>seconds</span> <span class='hs-varid'>secfrac</span>
<a name="line-108"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>ratval</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>toRational</span> <span class='hs-varid'>x</span>
<a name="line-109"></a> <span class='hs-varid'>seconds</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>floor</span> <span class='hs-varid'>ratval</span>
<a name="line-110"></a> <span class='hs-varid'>secfrac</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>floor</span> <span class='hs-varop'>$</span> <span class='hs-layout'>(</span><span class='hs-varid'>ratval</span> <span class='hs-comment'>-</span> <span class='hs-layout'>(</span><span class='hs-varid'>seconds</span> <span class='hs-varop'>%</span> <span class='hs-num'>1</span><span class='hs-layout'>)</span> <span class='hs-layout'>)</span> <span class='hs-varop'>*</span> <span class='hs-varid'>picosecondfactor</span>
<a name="line-111"></a> <span class='hs-varid'>picosecondfactor</span> <span class='hs-keyglyph'>=</span> <span class='hs-num'>10</span> <span class='hs-varop'>^</span> <span class='hs-num'>12</span>
<a name="line-112"></a>
<a name="line-113"></a><a name="clockTimeToEpoch"></a><span class='hs-comment'>{- | Converts a ClockTime to something represented with an arbitrary Real.
<a name="line-114"></a>The result could be treated as a CTime from Foreign.C.Types or EpochTime from
<a name="line-115"></a>System.Posix.Types. The inverse of 'epochToClockTime'.
<a name="line-116"></a>
<a name="line-117"></a>Fractions of a second are not preserved by this function. -}</span>
<a name="line-118"></a><span class='hs-definition'>clockTimeToEpoch</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Num</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>ClockTime</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>a</span>
<a name="line-119"></a><span class='hs-definition'>clockTimeToEpoch</span> <span class='hs-layout'>(</span><span class='hs-conid'>TOD</span> <span class='hs-varid'>sec</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fromInteger</span> <span class='hs-varid'>sec</span>
<a name="line-120"></a>
<a name="line-121"></a><a name="renderSecs"></a><span class='hs-comment'>{- | Render a number of seconds as a human-readable amount. Shows the two
<a name="line-122"></a>most significant places. For instance:
<a name="line-123"></a>
<a name="line-124"></a>>renderSecs 121 = "2m1s"
<a name="line-125"></a>
<a name="line-126"></a>See also 'renderTD' for a function that works on a TimeDiff.
<a name="line-127"></a>-}</span>
<a name="line-128"></a><span class='hs-definition'>renderSecs</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Integer</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span>
<a name="line-129"></a><span class='hs-definition'>renderSecs</span> <span class='hs-varid'>i</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>renderTD</span> <span class='hs-varop'>$</span> <span class='hs-varid'>diffClockTimes</span> <span class='hs-layout'>(</span><span class='hs-conid'>TOD</span> <span class='hs-varid'>i</span> <span class='hs-num'>0</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-conid'>TOD</span> <span class='hs-num'>0</span> <span class='hs-num'>0</span><span class='hs-layout'>)</span>
<a name="line-130"></a>
<a name="line-131"></a><a name="renderTD"></a><span class='hs-comment'>{- | Like 'renderSecs', but takes a TimeDiff instead of an integer second
<a name="line-132"></a>count. -}</span>
<a name="line-133"></a><span class='hs-definition'>renderTD</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>TimeDiff</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span>
<a name="line-134"></a><span class='hs-definition'>renderTD</span> <span class='hs-varid'>itd</span> <span class='hs-keyglyph'>=</span>
<a name="line-135"></a> <span class='hs-keyword'>case</span> <span class='hs-varid'>workinglist</span> <span class='hs-keyword'>of</span>
<a name="line-136"></a> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>-></span> <span class='hs-str'>"0s"</span>
<a name="line-137"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>concat</span> <span class='hs-varop'>.</span> <span class='hs-varid'>map</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-layout'>(</span><span class='hs-varid'>q</span><span class='hs-layout'>,</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>show</span> <span class='hs-varid'>q</span> <span class='hs-varop'>++</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>s</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>)</span> <span class='hs-varop'>$</span> <span class='hs-varid'>workinglist</span>
<a name="line-138"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>td</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>normalizeTimeDiff</span> <span class='hs-varid'>itd</span>
<a name="line-139"></a> <span class='hs-varid'>suffixlist</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"yMdhms"</span>
<a name="line-140"></a> <span class='hs-varid'>quantlist</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-layout'>(</span><span class='hs-conid'>TimeDiff</span> <span class='hs-varid'>y</span> <span class='hs-varid'>mo</span> <span class='hs-varid'>d</span> <span class='hs-varid'>h</span> <span class='hs-varid'>m</span> <span class='hs-varid'>s</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>y</span><span class='hs-layout'>,</span> <span class='hs-varid'>mo</span><span class='hs-layout'>,</span> <span class='hs-varid'>d</span><span class='hs-layout'>,</span> <span class='hs-varid'>h</span><span class='hs-layout'>,</span> <span class='hs-varid'>m</span><span class='hs-layout'>,</span> <span class='hs-varid'>s</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>)</span> <span class='hs-varid'>td</span>
<a name="line-141"></a> <span class='hs-varid'>zippedlist</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>zip</span> <span class='hs-varid'>quantlist</span> <span class='hs-varid'>suffixlist</span>
<a name="line-142"></a> <span class='hs-comment'>-- Drop all leading elements that are 0, then take at most 2</span>
<a name="line-143"></a> <span class='hs-varid'>workinglist</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>take</span> <span class='hs-num'>2</span> <span class='hs-varop'>.</span> <span class='hs-varid'>dropWhile</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-layout'>(</span><span class='hs-varid'>q</span><span class='hs-layout'>,</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>q</span> <span class='hs-varop'>==</span> <span class='hs-num'>0</span><span class='hs-layout'>)</span> <span class='hs-varop'>$</span> <span class='hs-varid'>zippedlist</span>
<a name="line-144"></a>
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