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      <h1>SRFI 285: Dates and Times</h1>
      <p class="authors">by Peter McGoron (steward, corresponding author), John Cowan (original design), Daphne Preston-Kendal (design and specification), and Arvydas Silanskas (implementation)</p>
      <p class="based-on"></p>
      <p class="status">status: <em>draft</em> (2026-09-20)</p>
      <p class="keywords">keywords: <a href="https://srfi.schemers.org/?keywords=data-structure">Data Structure</a></p><span class="see-also">See also <a href="/srfi-19/">SRFI 19: Time Data Types and Procedures</a> and <a href="/srfi-174/">SRFI 174: POSIX Timespecs</a>.</span>
      <p class="library-name">library name: date-and-time</p>
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      <h2>Abstract</h2><p>   This SRFI details an API for storing and manipluating dates and times.   This SRFI decomposes dates and times into dates (a count of days in the   proleptic Gregorian calendar), clock times (time of day, independent of   time zone), moments (instants in TAI), timezones (a possibly dynamic   offset from UTC), timestamps (a date, clock time,and timezone), and   time deltas (measurement of elapsed time). By doing this, a Scheme   program can operate on days in different calendars and timestamps in   different timezones. </p></body></html>