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SVNBugCommentTime (UTC)
2381Redefine datetimes to be stricter. Merge the two definitions of timezoned datetimes.2008-10-30 00:21
Index: source
===================================================================
--- source	(revision 2380)
+++ source	(revision 2381)
@@ -1953,58 +1953,150 @@
   href="#refsGREGORIAN">[GREGORIAN]</a></p>
 
 
-  <h5>Specific moments in time</h5>
+  <h5>Global dates and times</h5>
 
-  <p class="XXX">This syntax is going to be tightened up and
-  made almost exactly the same as the <span>valid UTC date and time
-  string</span> syntax, with the exception of allowing time zones. In
-  fact what we might do is allow time zones in general, use the same
-  parser, etc, but require that UAs always use the UTC time zone when
-  synthesizing datetimes for form submission.</p>
+  <p>A <dfn title="concept-datetime">global date and time</dfn>
+  consists of a specific Gregorian date, consisting of a year, a
+  month, a day, an hour, a minute, a second, and a fraction of a
+  second, expressed with a time zone, consisting of a number of hours
+  and minutes. <a href="#refsGREGORIAN">[GREGORIAN]</a></p>
 
-  <p>A string is a <dfn>valid datetime</dfn> if it has four digits
-  (representing the year), a literal hyphen, two digits (representing
-  the month), a literal hyphen, two digits (representing the day),
-  optionally some spaces, either a literal T or a space, optionally
-  some more spaces, two digits (for the hour), a colon, two digits
-  (the minutes), optionally the seconds (which, if included, must
-  consist of another colon, two digits (the integer part of the
-  seconds), and optionally a decimal point followed by one or more
-  digits (for the fractional part of the seconds)), optionally some
-  spaces, and finally either a literal Z (indicating the time zone is
-  UTC), or, a plus sign or a minus sign followed by two digits, a
-  colon, and two digits (for the sign, the hours and minutes of the
-  timezone offset respectively); with the month-day combination being
-  a valid date in the given year according to the Gregorian calendar,
-  the hour values (<var title="">h</var>) being in the range
-  0&nbsp;&le;&nbsp;<var title="">h</var>&nbsp;&le;&nbsp;23, the minute
-  values (<var title="">m</var>) in the range 0&nbsp;&le;&nbsp;<var
-  title="">m</var>&nbsp;&le;&nbsp;59, and the second value (<var
-  title="">s</var>) being in the range 0&nbsp;&le;&nbsp;<var
-  title="">h</var>&nbsp;&lt;&nbsp;60. <a
-  href="#refsGREGORIAN">[GREGORIAN]</a></p>
-
   <!--XXX [GREGORIAN] should point to
   <dd id="refsGREGORIAN">[GREGORIAN]</dd>
   <dd>(Non-normative) <cite>Inter Gravissimas</cite>, A. Lilius, C. Clavius. Gregory XIII Papal Bulls, February 1582.</dd>
   -->
 
-  <p>The digits must be characters in the range U+0030 DIGIT ZERO (0)
-  to U+0039 DIGIT NINE (9), the hyphens must be a U+002D HYPHEN-MINUS
-  characters, the T must be a U+0054 LATIN CAPITAL LETTER T, the
-  colons must be U+003A COLON characters, the decimal point must be a
-  U+002E FULL STOP, the Z must be a U+005A LATIN CAPITAL LETTER Z, the
-  plus sign must be a U+002B PLUS SIGN, and the minus U+002D (same as
-  the hyphen).</p>
+  <p>A string is a <dfn>valid global date and time string</dfn> if it
+  has the components in the following list, in the given order, and if
+  the components in the list follow the constraints given after the
+  list:</p>
 
+  <ol>
+
+   <li>Four or more digits (representing the year)</li>
+
+   <li>A U+002D HYPHEN-MINUS character (-).</li>
+
+   <li>Two digits (representing the month)</li>
+
+   <li>A U+002D HYPHEN-MINUS character (-).</li>
+
+   <li>Two digits (representing the day)</li>
+
+   <li>A U+0054 LATIN CAPITAL LETTER T character.</li>
+
+   <li>Two digits (representing the hour)</li>
+
+   <li>A U+003A COLON character (:).</li>
+
+   <li>Two digits (representing the minutes)</li>
+
+   <li>Optionally:
+
+    <ol>
+
+     <li>A U+003A COLON character (:).</li>
+
+     <li>Two digits (representing the integer part of the seconds)</li>
+
+     <li>Optionally:
+
+      <ol>
+
+       <li>A 002E FULL STOP character (.)</li>
+
+       <li>One or more digits (representing the fractional part of the seconds)</li>
+
+      </ol>
+
+     </li>
+
+    </ol>
+
+   </li>
+
+   <li>Either:
+
+    <ul>
+
+     <li>A U+005A LATIN CAPITAL LETTER Z character (indicating the
+     time zone is UTC)</li>
+
+     <li>Or:
+
+      <ol>
+
+       <li>Either a U+002B PLUS SIGN character (+) or a U+002D
+       HYPHEN-MINUS (-) character (the sign of the timezone
+       offset)</li>
+
+       <li>Two digits (representing the hours component of the timezone offset)</li>
+
+       <li>A U+003A COLON character (:).</li>
+
+       <li>Two digits (representing the minutes component of the timezone offset)</li>
+
+      </ol>
+
+     </li>
+
+    </ul>
+
+   </li>
+
+  </ol>
+
+  <p>The aforementioned constraints are:</p>
+
+  <ul>
+
+   <li>The month <var title="">m</var> must be in the range
+   0&nbsp;&le;&nbsp;<var title="">m</var>&nbsp;&le;&nbsp;12.</li>
+
+   <li>The day <var title="">d</var> must be in the range
+   0&nbsp;&le;&nbsp;<var title="">d</var>&nbsp;&le;&nbsp;<var
+   title="">D</var> where <var title="">D</var> is the <span
+   title="number of days in month month of year year">number of days
+   in the given month and year</span>.</li>
+
+   <li>The hour <var title="">h</var> must be in the range
+   0&nbsp;&le;&nbsp;<var title="">h</var>&nbsp;&le;&nbsp;23.</li>
+
+   <li>The minute <var title="">m</var> must be in the range
+   0&nbsp;&le;&nbsp;<var title="">m</var>&nbsp;&le;&nbsp;59.</li>
+
+   <li>If present, the second <var title="">s</var> (consisting of the
+   integer part and its fractional part) must be in the range
+   0&nbsp;&le;&nbsp;<var title="">s</var>&nbsp;&lt;&nbsp;60.  (The
+   values 60 and 61 are not allowed: leap seconds cannot be
+   represented by datetime values.)</li>
+
+   <li>If present, the time zone hour <var title="">h</var> must be in
+   the range 0&nbsp;&le;&nbsp;<var
+   title="">h</var>&nbsp;&le;&nbsp;23. (However, in practice, time
+   zones do not currently ever have an hour component greater than
+   14.)</li>
+
+   <li>If present, the time zone minute <var title="">m</var> must be
+   in the range 0&nbsp;&le;&nbsp;<var
+   title="">m</var>&nbsp;&le;&nbsp;59. (However, in practice, time
+   zones do not currently ever have a minute component other than 0, 30,
+   or 45.)</li>
+
+  </ul>
+
+  <p>The digits must be characters in the range U+0030 DIGIT ZERO to
+  U+0039 DIGIT NINE, used to express numbers in base ten.</p>
+
   <div class="example">
 
    <p>The following are some examples of dates written as <span
-   title="valid datetime">valid datetimes</span>.</p>
+   title="valid global date and time string">valid global date and
+   time strings</span>.</p>
 
    <dl>
 
-    <dt>"<code>0037-12-13 00:00 Z</code>"</dt>
+    <dt>"<code>0037-12-13T00:00Z</code>"</dt>
 
     <dd>Midnight UTC on the birthday of Nero (the Roman Emperor).</dd>
 
@@ -2014,11 +2106,12 @@
     zone in use on the east coast of North America during daylight
     saving time.</dd>
 
-    <dt>"<code>8592-01-01 T 02:09 +02:09</code>"</dt>
+    <dt>"<code>8592-01-01T02:09+02:09</code>"</dt>
 
     <dd>Midnight UTC on the 1st of January, 8592. The time zone
     associated with that time is two hours and nine minutes ahead of
-    UTC.</dd>
+    UTC, which is not a real time zone currently, but is nonetheless
+    allowed.</dd>
 
    </dl>
 
@@ -2042,8 +2135,8 @@
 
     <li>The time and timezone components are not optional.</li>
 
-    <li>Dates before the year 0 or after the year 9999 can't be
-    represented as a datetime in this version of HTML.</li>
+    <li>Dates before the year zero can't be represented as a datetime
+    in this version of HTML.</li>
 
     <li>Time zones differ based on daylight savings time.</li>
 
@@ -2051,16 +2144,11 @@
 
   </div>
 
-  <p class="note">Conformance checkers can use the algorithm below to
-  determine if a datetime is a valid datetime or not.</p>
-
-  <p>To <dfn id="datetime-parser">parse a string as a datetime
-  value</dfn>, a user agent must apply the following algorithm to the
-  string. This will either return a time in UTC, with associated
+  <p>The rules to <dfn>parse a global date and time string</dfn> are
+  as follows. This will either return a time in UTC, with associated
   timezone information for round tripping or display purposes, or
-  nothing, indicating the value is not a <span>valid
-  datetime</span>. If at any point the algorithm says that it "fails",
-  this means that it returns nothing.</p>
+  nothing. If at any point the algorithm says that it "fails", this
+  means that it is aborted at that point and returns nothing.</p>
 
   <ol>
 
@@ -2073,9 +2161,9 @@
 
    <li><p><span>Collect a sequence of characters</span> in the range
    U+0030 DIGIT ZERO (0) to U+0039 DIGIT NINE (9). If the collected
-   sequence is not exactly four characters long, then fail. Otherwise,
-   interpret the resulting sequence as a base-ten integer. Let that
-   number be the <var title="">year</var>.</p></li>
+   sequence is not at least four characters long, then
+   fail. Otherwise, interpret the resulting sequence as a base-ten
+   integer. Let that number be the <var title="">year</var>.</p></li>
 
    <li><p>If <var title="">position</var> is beyond the end of <var
    title="">input</var> or if the character at <var
@@ -2090,7 +2178,8 @@
    number be the <var title="">month</var>.</p></li>
 
    <li>If <var title="">month</var> is not a number in the range
-   1&nbsp;&le;&nbsp;<var title="">month</var>&nbsp;&le;&nbsp;12, then fail.</li>
+   1&nbsp;&le;&nbsp;<var title="">month</var>&nbsp;&le;&nbsp;12, then
+   fail.</li>
 
    <li><p>Let <var title="">maxday</var> be the <span>number of days
    in month <var title="">month</var> of year <var
@@ -2112,11 +2201,11 @@
    1&nbsp;&le;&nbsp;<var title="">month</var>&nbsp;&le;&nbsp;<var
    title="">maxday</var>, then fail.</li>
 
-   <li><p><span>Collect a sequence of characters</span> that are
-   either U+0054 LATIN CAPITAL LETTER T characters or <span
-   title="space character">space characters</span>. If the collected
-   sequence is zero characters long, or if it contains more than one
-   U+0054 LATIN CAPITAL LETTER T character, then fail.</p></li>
+   <li><p>If <var title="">position</var> is beyond the end of <var
+   title="">input</var> or if the character at <var
+   title="">position</var> is not a U+0054 LATIN CAPITAL LETTER T
+   character then fail. Otherwise, move <var title="">position</var>
+   forwards one character.</p></li>
 
    <li><p><span>Collect a sequence of characters</span> in the range
    U+0030 DIGIT ZERO (0) to U+0039 DIGIT NINE (9). If the collected
@@ -2125,13 +2214,14 @@
    number be the <var title="">hour</var>.</p></li>
 
    <li>If <var title="">hour</var> is not a number in the range
-   0&nbsp;&le;&nbsp;<var title="">hour</var>&nbsp;&le;&nbsp;23, then fail.</li>
+   0&nbsp;&le;&nbsp;<var title="">hour</var>&nbsp;&le;&nbsp;23, then
+   fail.</li>
 
    <li><p>If <var title="">position</var> is beyond the end of <var
    title="">input</var> or if the character at <var
-   title="">position</var> is not a U+003A COLON character,
-   then fail. Otherwise, move <var title="">position</var> forwards
-   one character.</p></li>
+   title="">position</var> is not a U+003A COLON character, then
+   fail. Otherwise, move <var title="">position</var> forwards one
+   character.</p></li>
 
    <li><p><span>Collect a sequence of characters</span> in the range
    U+0030 DIGIT ZERO (0) to U+0039 DIGIT NINE (9). If the collected
@@ -2140,7 +2230,8 @@
    number be the <var title="">minute</var>.</p></li>
 
    <li>If <var title="">minute</var> is not a number in the range
-   0&nbsp;&le;&nbsp;<var title="">minute</var>&nbsp;&le;&nbsp;59, then fail.</li>
+   0&nbsp;&le;&nbsp;<var title="">minute</var>&nbsp;&le;&nbsp;59, then
+   fail.</li>
 
    <li><p>Let <var title="">second</var> be a string with the value
    "0".</p></li>
@@ -2148,9 +2239,11 @@
    <li><p>If <var title="">position</var> is beyond the end of <var
    title="">input</var>, then fail.</p></li>
 
-   <li><p>If the character at <var title="">position</var> is a U+003A
-   COLON, then:</p>
+   <li>
 
+    <p>If the character at <var title="">position</var> is a U+003A
+    COLON, then run these substeps:</p>
+
     <ol>
 
      <li><p>Advance <var title="">position</var> to the next character
@@ -2177,41 +2270,38 @@
    </li>
 
    <li><p>Interpret <var title="">second</var> as a base-ten number
-   (possibly with a fractional part). Let that number be <var
-   title="">second</var> instead of the string version.</p></li>
+   (possibly with a fractional part). Let <var title="">second</var>
+   be that number instead of the string version.</p></li>
 
    <li>If <var title="">second</var> is not a number in the range
    0&nbsp;&le;&nbsp;<var title="">second</var>&nbsp;&lt;&nbsp;60, then
-   fail. (The values 60 and 61 are not allowed: leap seconds cannot be
-   represented by datetime values.)</li>
+   fail.</li>
 
    <li><p>If <var title="">position</var> is beyond the end of <var
    title="">input</var>, then fail.</p></li>
 
-   <li><p><span>Skip whitespace</span>.</p></li>
+   <li>
 
-   <li><p>If the character at <var title="">position</var> is a
-   U+005A LATIN CAPITAL LETTER Z, then:</p>
+    <p>If the character at <var title="">position</var> is a U+005A
+    LATIN CAPITAL LETTER Z, then:</p>
 
     <ol>
 
-     <li><p>Let <var title="">timezone<sub title="">hours</sub></var> be
-     0.</p></li>
+     <li><p>Let <var title="">timezone<sub title="">hours</sub></var>
+     be 0.</p></li>
 
-     <li><p>Let <var title="">timezone<sub title="">minutes</sub></var> be
-     0.</p></li>
+     <li><p>Let <var title="">timezone<sub
+     title="">minutes</sub></var> be 0.</p></li>
 
      <li><p>Advance <var title="">position</var> to the next character
      in <var title="">input</var>.</p></li>
 
     </ol>
 
-   </li>
+    <p>Otherwise, if the character at <var title="">position</var> is
+    either a U+002B PLUS SIGN ("+") or a U+002D HYPHEN-MINUS ("-"),
+    then:</p>
 
-   <li><p>Otherwise, if the character at <var title="">position</var>
-   is either a U+002B PLUS SIGN ("+") or a U+002D HYPHEN-MINUS ("-"),
-   then:</p>
-
     <ol>
 
      <li><p>If the character at <var title="">position</var> is a
@@ -2226,13 +2316,13 @@
      U+0030 DIGIT ZERO (0) to U+0039 DIGIT NINE (9). If the collected
      sequence is not exactly two characters long, then
      fail. Otherwise, interpret the resulting sequence as a base-ten
-     integer. Let that number be the <var
-     title="">timezone<sub title="">hours</sub></var>.</p></li>
+     integer. Let that number be the <var title="">timezone<sub
+     title="">hours</sub></var>.</p></li>
 
-     <li>If <var title="">timezone<sub title="">hours</sub></var> is not a
-     number in the range 0&nbsp;&le;&nbsp;<var
-     title="">timezone<sub title="">hours</sub></var>&nbsp;&le;&nbsp;23, then
-     fail.</li>
+     <li>If <var title="">timezone<sub title="">hours</sub></var> is
+     not a number in the range 0&nbsp;&le;&nbsp;<var
+     title="">timezone<sub
+     title="">hours</sub></var>&nbsp;&le;&nbsp;23, then fail.</li>
 
      <li>If <var title="">sign</var> is "negative", then negate <var
      title="">timezone<sub title="">hours</sub></var>.</li>
@@ -2247,13 +2337,13 @@
      U+0030 DIGIT ZERO (0) to U+0039 DIGIT NINE (9). If the collected
      sequence is not exactly two characters long, then
      fail. Otherwise, interpret the resulting sequence as a base-ten
-     integer. Let that number be the <var
-     title="">timezone<sub title="">minutes</sub></var>.</p></li>
+     integer. Let that number be the <var title="">timezone<sub
+     title="">minutes</sub></var>.</p></li>
 
-     <li>If <var title="">timezone<sub title="">minutes</sub></var> is not a
-     number in the range 0&nbsp;&le;&nbsp;<var
-     title="">timezone<sub title="">minutes</sub></var>&nbsp;&le;&nbsp;59, then
-     fail.</li>
+     <li>If <var title="">timezone<sub title="">minutes</sub></var> is
+     not a number in the range 0&nbsp;&le;&nbsp;<var
+     title="">timezone<sub
+     title="">minutes</sub></var>&nbsp;&le;&nbsp;59, then fail.</li>
 
      <li>If <var title="">sign</var> is "negative", then negate <var
      title="">timezone<sub title="">minutes</sub></var>.</li>
@@ -2285,20 +2375,6 @@
   </ol>
 
 
-  <h5>UTC dates and times</h5>
-
-  <p>A <dfn title="concept-datetime">UTC date and time</dfn> consists
-  of a specific Gregorian date expressed relative to the UTC timezone,
-  consisting of a year, a month, a day, an hour, a minute, a second,
-  and a fraction of a second. <a
-  href="#refsGREGORIAN">[GREGORIAN]</a></p>
-
-  <p class="XXX">... <dfn>valid UTC date and time string</dfn></p>
-
-  <p class="XXX">... rules to <dfn>parse a UTC date and time
-  string</dfn></p>
-
-
   <h5>Local dates and times</h5>
 
   <p>A <dfn title="concept-datetime-local">local date and time</dfn>
@@ -14411,17 +14487,18 @@
   attribute may be used to specify the time and date of the change.</p>
 
   <p>If present, the <code title="attr-mod-datetime">datetime</code>
-  attribute must be a <span>valid datetime</span> value.</p>
+  attribute must be a <span>valid global date and time string</span>
+  value.</p>
 
   <p>User agents must parse the <code
   title="attr-mod-datetime">datetime</code> attribute according to the
-  <span>parse a string as a datetime value</span> algorithm. If that
+  <span>parse a global date and time string</span> algorithm. If that
   doesn't return a time, then the modification has no associated
   timestamp (the value is non-conforming; it is not a <span>valid
-  datetime</span>). Otherwise, the modification is marked as having
-  been made at the given datetime. User agents should use the
-  associated timezone information to determine which timezone to
-  present the given datetime in.</p>
+  global date and time string</span>). Otherwise, the modification is
+  marked as having been made at the given datetime. User agents should
+  use the associated timezone information to determine which timezone
+  to present the given datetime in.</p>
 
   <p>The <code>ins</code> and <code>del</code> elements must implement
   the <code>HTMLModElement</code> interface:</p>
@@ -27032,40 +27109,46 @@
 
   <p>The <code>input</code> element represents a control for setting
   the element's <span title="concept-fe-value">value</span> to a
-  string representing a specific <span title="concept-datetime">UTC
+  string representing a specific <span title="concept-datetime">global
   date and time</span>. User agents may display the date and time in
   whatever timezone is appropriate for the user.</p>
 
   <p>If the element is <i title="concept-input-mutable">mutable</i>,
   the user agent should allow the user to change the <span
-  title="concept-datetime">UTC date and time</span> represented by its
-  <span title="concept-fe-value">value</span>, as obtained by <span
-  title="parse a UTC date and time string">parsing a UTC date and
-  time</span> from it. User agents must not allow the user to set the
-  <span title="concept-fe-value">value</span> to a string that is not
-  a <span>valid UTC date and time string</span>. If the user agent
-  provides a user interface for selecting a <span
-  title="concept-datetime">UTC date and time</span>, then the <span
+  title="concept-datetime">global date and time</span> represented by
+  its <span title="concept-fe-value">value</span>, as obtained by
+  <span title="parse a global date and time string">parsing a global
+  date and time</span> from it. User agents must not allow the user to
+  set the <span title="concept-fe-value">value</span> to a string that
+  is not a <span>valid global date and time string</span> expressed in
+  UTC, though user agents may allow the user to set and view the time
+  in another timezone and silently translate the time to and from the
+  UTC timezone in the <span title="concept-fe-value">value</span>. If
+  the user agent provides a user interface for selecting a <span
+  title="concept-datetime">global date and time</span>, then the <span
   title="concept-fe-value">value</span> must be set to a <span>valid
-  UTC date and time string</span> representing the user's
-  selection. User agents should allow the user to set the <span
+  global date and time string</span> expressed in UTC representing the
+  user's selection. User agents should allow the user to set the <span
   title="concept-fe-value">value</span> to the empty string.</p>
 
   <p>The <code title="attr-input-value">value</code> attribute, if
-  specified, must have a value that is a <span>valid UTC date and time
-  string</span>.</p> <!-- ok to set out-of-range value, we never know
-  when we might have to represent bogus input -->
+  specified, must have a value that is a <span>valid global date and
+  time string</span>.</p> <!-- ok to set out-of-range value, we never
+  know when we might have to represent bogus input -->
 
   <p><strong>The <span>value sanitization algorithm</span> is as
   follows:</strong> If the <span title="concept-fe-value">value</span>
-  of the element is not a <span>valid UTC date and time string</span>,
-  then set it to the empty string instead.</p>
+  of the element is a <span>valid global date and time string</span>,
+  then adjust the time so that the <span
+  title="concept-fe-value">value</span> represents the same point in
+  time but expressed in the UTC timezone, otherwise, set it to the
+  empty string instead.</p>
 
   <p>The <code title="attr-input-min">min</code> attribute, if
-  specified, must have a value that is a <span>valid UTC date and time
-  string</span>. The <code title="attr-input-max">max</code>
-  attribute, if specified, must have a value that is a <span>valid UTC
-  date and time string</span>.</p>
+  specified, must have a value that is a <span>valid global date and
+  time string</span>. The <code title="attr-input-max">max</code>
+  attribute, if specified, must have a value that is a <span>valid
+  global date and time string</span>.</p>
 
   <p>The <code title="attr-input-step">step</code> attribute is
   expressed in seconds. The <span
@@ -27077,28 +27160,28 @@
   <p>When the element is <span>suffering from a step mismatch</span>,
   the user agent may round the element's <span
   title="concept-fe-value">value</span> to the nearest <span
-  title="concept-datetime">UTC date and time</span> for which the
+  title="concept-datetime">global date and time</span> for which the
   element would not <span title="suffering from a step
   mismatch">suffer from a step mismatch</span>.</p>
 
   <p><strong>The <span
   title="concept-input-value-string-number">algorithm to convert a
   string to a number</span>, given a string <var title="">input</var>,
-  is as follows:</strong> If <span title="parse a UTC date and time
-  string">parsing a UTC date and time</span> from <var
+  is as follows:</strong> If <span title="parse a global date and time
+  string">parsing a global date and time</span> from <var
   title="">input</var> results in an error, then return an error;
   otherwise, return the number of milliseconds elapsed from midnight
   UTC on the morning of 1970-01-01 (the time represented by the value
   "<code title="">1970-01-01T00:00:00.0Z</code>") to the parsed <span
-  title="concept-datetime">UTC date and time</span>, ignoring leap
+  title="concept-datetime">global date and time</span>, ignoring leap
   seconds.</p>
 
   <p><strong>The <span
   title="concept-input-value-number-string">algorithm to convert a
   number to a string</span>, given a number <var title="">input</var>,
-  is as follows:</strong> Return a <span>valid UTC date and time
-  string</span> that represents the <span
-  title="concept-datetime">date and time in UTC</span> that is <var
+  is as follows:</strong> Return a <span>valid global date and time
+  string</span> expressed in UTC that represents the <span
+  title="concept-datetime">global date and time</span> that is <var
   title="">input</var> milliseconds after midnight UTC on the morning
   of 1970-01-01 (the time represented by the value "<code
   title="">1970-01-01T00:00:00.0Z</code>").</p>
@@ -27107,18 +27190,19 @@
   title="concept-input-value-string-date">algorithm to convert a
   string to a <code>Date</code> object</span>, given a string <var
   title="">input</var>, is as follows:</strong> If <span title="parse
-  a UTC date and time string">parsing a UTC date and time</span> from
-  <var title="">input</var> results in an error, then return an error;
-  otherwise, return a <code>Date</code> object representing the parsed
-  <span title="concept-datetime">UTC date and time</span>.</p>
+  a global date and time string">parsing a global date and time</span>
+  from <var title="">input</var> results in an error, then return an
+  error; otherwise, return a <code>Date</code> object representing the
+  parsed <span title="concept-datetime">global date and time</span>,
+  expressed in UTC.</p>
 
   <p><strong>The <span
   title="concept-input-value-date-string">algorithm to convert a
   <code>Date</code> object to a string</span>, given a
   <code>Date</code> object <var title="">input</var>, is as
-  follows:</strong> Return a <span>valid UTC date and time
-  string</span> that represents the <span
-  title="concept-datetime">date and time in UTC</span> that is
+  follows:</strong> Return a <span>valid global date and time
+  string</span> expressed in UTC that represents the <span
+  title="concept-datetime">global date and time</span> that is
   represented by <var title="">input</var>.</p>
 
   <div class="bookkeeping">

|