Lady’s Gitweb - Vocab/blob - data/datatype_properties/¦n

   1 <?xml version="1.0"?>
   2 <!--
   3 SPDX-FileCopyrightText: 2025 Lady <https://www.ladys.computer/about/#lady>
   4 SPDX-License-Identifier: CC0-1.0
   5 -->
   6 <!DOCTYPE DatatypeProperty SYSTEM "../../DTD">
   7 <DatatypeProperty functional="yes" status="testing">
   8         <label xml:lang="en">local notation</label>
   9         <comment xml:lang="en">
  10                 <p>
  11                         An integer, string, or time·stamp which identifies and orders a thing within a given context.
  12                 </p>
  13                 <p>
  14                         String values can either be valid <resource name="xsd:NCName"/>¦s or else have the form of a <resource name="xsd:gYearMonth"/> or <resource name="xsd:date"/> with no time·zone component.
  15                         These possibilities were selected to ensure that the lexical forms of each type are disjoint.
  16                 </p>
  17                 <p>
  18                         Because this property is functional, a <resource name="Proxy"/> must be used when local notation depends on a particular context.
  19                 </p>
  20                 <p>
  21                         Correctly ordering things by local notation involves two steps.
  22                         First, the local notation must be split into a tuple of two parts :⁠—
  23                 </p>
  24                 <list>
  25                         <item>
  26                                 <p>
  27                                         If it is a string which begins with an underscore and contains another underscore which is followed by a period :⁠—
  28                                 </p>
  29                                 <list>
  30                                         <item>
  31                                                 <p>
  32                                                         Let <var>base</var> be the portion of the string which follows the initial underscore and precedes the first successive underscore‐period sequence.
  33                                                 </p>
  34                                         </item>
  35                                         <item>
  36                                                 <p>
  37                                                         Let <var>mod</var> be the portion of the string which follows that same underscore‐period sequence.
  38                                                 </p>
  39                                         </item>
  40                                         <item>
  41                                                 <p>
  42                                                         If <var>mod</var> is not itself a valid canonical representation for some local notation, then the first value of the tuple is the original string, and the second value is the empty string.
  43                                                 </p>
  44                                         </item>
  45                                         <item>
  46                                                 <p>
  47                                                         Otherwise, if <var>base</var> is a valid <resource name="xsd:NCName"/> or else has the form of a <resource name="xsd:gYearMonth"/> or <resource name="xsd:date"/> with no time·zone component, then the tuple is {<var>base</var>, <var>mod</var>}.
  48                                                 </p>
  49                                         </item>
  50                                         <item>
  51                                                 <p>
  52                                                         Otherwise, if <var>base</var> is the canonical representation of some <resource name="xsd:integer"/> <var>int</var>, then the tuple is {<var>int</var>, <var>mod</var>}.
  53                                                 </p>
  54                                         </item>
  55                                         <item>
  56                                                 <p>
  57                                                         Otherwise, make the following modifications to <var>base</var> :⁠—
  58                                                 </p>
  59                                                 <list>
  60                                                         <item>
  61                                                                 <p>
  62                                                                         Replace all underscores in <var>base</var> with plusses.
  63                                                                 </p>
  64                                                         </item>
  65                                                         <item>
  66                                                                 <p>
  67                                                                         If <var>base</var> contains <code>T</code>, replace the first two periods in <var>base</var> which follow <code>T</code> (if present) with colons.
  68                                                                 </p>
  69                                                         </item>
  70                                                         <item>
  71                                                                 <p>
  72                                                                         If <var>base</var> ends in a digit, replace the final remaining period in <var>base</var> (if present) with a colon.
  73                                                                 </p>
  74                                                         </item>
  75                                                 </list>
  76                                                 <p>
  77                                                         If, after making the above substitutions, <var>base</var> is the canonical representation of some <resource name="xsd:dateTimeStamp"/> <var>time</var>, then the tuple is {<var>time</var>, <var>mod</var>}.
  78                                                 </p>
  79                                         </item>
  80                                         <item>
  81                                                 <p>
  82                                                         Otherwise, the first value of the tuple is the original string, and the second value is the empty string.
  83                                                 </p>
  84                                         </item>
  85                                 </list>
  86                         </item>
  87                         <item>
  88                                 <p>
  89                                         Otherwise, the first value of the tuple is the original string, and the second value is the empty string.
  90                                 </p>
  91                         </item>
  92                 </list>
  93                 <p>
  94                         Then, the values of the tuples can be sorted according to the following rules, with the first part taking priority over the second :⁠—
  95                 </p>
  96                 <list>
  97                         <item>
  98                                 <p>
  99                                         Empty strings are always sorted first.
 100                                 </p>
 101                         </item>
 102                         <item>
 103                                 <p>
 104                                         Integers are sorted by numeric value and come after empty strings.
 105                                 </p>
 106                         </item>
 107                         <item>
 108                                 <p>
 109                                         Time·stamps and strings which match <resource name="xsd:gYearMonth"/> or <resource name="xsd:date"/> come after integers, and are sorted according to their corresponding “time on timeline” values, with the following modifications :⁠—
 110                                 </p>
 111                                 <list>
 112                                         <item>
 113                                                 <p>
 114                                                         For <resource name="xsd:gYearMonth"/> values, the missing day component is treated as the first rather than the last day of the month
 115                                                 </p>
 116                                         </item>
 117                                         <item>
 118                                                 <p>
 119                                                         When the “time on timeline” value is the same, <resource name="xsd:gYearMonth"/> sorts before <resource name="xsd:date"/>, and <resource name="xsd:date"/> sorts before <resource name="xsd:dateTimeStamp"/>.
 120                                                 </p>
 121                                         </item>
 122                                         <item>
 123                                                 <p>
 124                                                         When the “time on timeline” value is the same for two <resource name="xsd:dateTimeStamp"/> values, they are sorted based on their timezone offsets in ascending order.
 125                                                 </p>
 126                                         </item>
 127                                 </list>
 128                         </item>
 129                         <item>
 130                                 <p>
 131                                         Strings which match <resource name="xsd:NCName"/> follow the above, and are sorted lexically by code·point value.
 132                                 </p>
 133                         </item>
 134                 </list>
 135                 <p>
 136                         The above algorithm effectively establishes a special microsyntax in which <code>_base_.mod</code> will always sort after <code>base</code>, regardless of <code>base</code>¦s type.
 137                         When <code>base</code> is a <resource name="xsd:dateTimeStamp"/>, a few reversible modifications need to be made in order to satisfy the <resource name="xsd:NCName"/> syntax :⁠—
 138                 </p>
 139                 <list>
 140                         <item>
 141                                 <p>
 142                                         Any colons in the time component or time·zone offset must be replaced with periods.
 143                                 </p>
 144                         </item>
 145                         <item>
 146                                 <p>
 147                                         A plus in the time·zone offset, if present, must be replaced with an underscore.
 148                                 </p>
 149                         </item>
 150                 </list>
 151         </comment>
 152         <subPropertyOf>
 153                 <resource name="dcterms:identifier"/>
 154         </subPropertyOf>
 155         <range>
 156                 <Datatype>
 157                         <unionOf>
 158                                 <resource name="xsd:integer"/>
 159                                 <resource name="xsd:NCName"/>
 160                                 <Datatype>
 161                                         <onDatatype>
 162                                                 <resource name="xsd:string"/>
 163                                         </onDatatype>
 164                                         <withRestrictions>
 165                                                 <pattern>[0-9]{4}(-[0-9]{2}){1,2}</pattern>
 166                                         </withRestrictions>
 167                                 </Datatype>
 168                                 <resource name="xsd:dateTimeStamp"/>
 169                         </unionOf>
 170                 </Datatype>
 171         </range>
 172 </DatatypeProperty>