ceph/src/boost/libs/property_map/doc/WritablePropertyMap.html

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   9 <Head>
  10 <Title>WritablePropertyMap</Title>
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  19 <H2><A NAME="concept:WritablePropertyMap"></A>
  20 Writable Property Map
  21 </H2>
  22
  23 A Writable Property Map has the capability of setting the value
  24 object associated with the given key object via the <tt>put()</tt>
  25 function.
  26
  27 <h3>Refinement of</h3>
  28
  29 <a href="../../utility/CopyConstructible.html">Copy Constructible</a>
  30
  31
  32 <h3>Notation</h3>
  33
  34 <Table>
  35 <TR>
  36 <TD><tt>PMap</tt></TD>
  37 <TD>A type that is a model of Writable Property Map.</TD>
  38 </TR>
  39 <TR>
  40 <TD><tt>pmap</tt></TD>
  41 <TD>An object of type <tt>PMap</tt>.</td>
  42 </TR>
  43 <TR>
  44 <TD><tt>key</tt></TD>
  45 <TD>An object of type <tt>boost::property_traits&lt;PMap&gt;::key_type</tt>.</td>
  46 </TR>
  47 <TR>
  48 <TD><tt>val</tt></TD>
  49 <TD>An object of type <tt>boost::property_traits&lt;PMap&gt;::value_type</tt>.</td>
  50 </TR>
  51 </table>
  52
  53 <h3>Associated Types</h3>
  54
  55 <table border>
  56
  57 <tr>
  58 <td>Value Type</td>
  59 <td><TT>boost::property_traits&lt;PMap&gt;::value_type</TT></td>
  60 <td>
  61 The type of the property.
  62 </td>
  63 </tr>
  64
  65 <tr>
  66 <td>Key Type</td>
  67 <td><TT>boost::property_traits&lt;PMap&gt;::key_type</TT></td>
  68 <td>
  69 The type of the key object used to look up the property. The property
  70 map may be templated on the key type, in which case this typedef
  71 can be <TT>void</TT>.
  72 </td>
  73 </tr>
  74
  75 <tr>
  76 <td>Property Map Category </td>
  77 <td><TT>boost::property_traits&lt;PMap&gt;::category</TT></td>
  78 <td>
  79 The category of the property: a type convertible to
  80 <TT>writable_property_map_tag</TT>.
  81 </td>
  82 </tr>
  83
  84 </table>
  85
  86
  87 <h3>Valid Expressions</h3>
  88
  89 <table border>
  90 <tr>
  91 <th>Name</th><th>Expression</th><th>Return Type</th><th>Description</th>
  92 </tr>
  93
  94 <tr>
  95 <td>Put Property Value<a href="#1">[1]</a></td>
  96 <TD><TT>put(pmap, key, val)</TT></TD>
  97 <TD><TT>void</TT></TD>
  98 <TD>
  99 Assign <TT>val</TT> to the property associated with <TT>k</TT>.
 100 </TD>
 101 </TR>
 102
 103 </TABLE>
 104
 105
 106 <h3>Notes</h3>
 107
 108 <a name="1">[1]</a> The function <tt>put()</tt> was originally named
 109 <tt>set()</tt>, but was changed to avoid name conflicts with the
 110 <tt>std::set</tt> class when using a compiler (Microsoft Visual C++)
 111 with non-standard name lookup rules. The following example demonstrates
 112 the problem.
 113 <pre>#include &lt;set&gt;
 114 using namespace std;
 115 namespace boost {
 116   void set() { }
 117 }</pre>
 118
 119
 120 <h3>Concept Checking Class</h3>
 121
 122 <pre>  template &lt;class PMap, class Key&gt;
 123   struct WritablePropertyMapConcept
 124   {
 125     typedef typename property_traits&lt;PMap&gt;::key_type key_type;
 126     typedef typename property_traits&lt;PMap&gt;::category Category;
 127     typedef boost::writable_property_map_tag WritableTag;
 128     void constraints() {
 129       function_requires&lt; ConvertibleConcept&lt;Category, WritableTag&gt; &gt;();
 130       put(pmap, k, val);
 131     }
 132     PMap pmap;
 133     Key k;
 134     typename property_traits&lt;PMap&gt;::value_type val;
 135   };</pre>
 136
 137 <h3>See Also</h3>
 138
 139 <a href="./property_map.html">Property map concepts</a>
 140
 141
 142 <br>
 143 <HR>
 144 <TABLE>
 145 <TR valign=top>
 146 <TD nowrap>Copyright &copy 2000</TD><TD>
 147 <a HREF="http://www.boost.org/people/jeremy_siek.htm">Jeremy Siek</a>, Univ.of Notre Dame (<A HREF="mailto:jsiek@lsc.nd.edu">jsiek@lsc.nd.edu</A>)
 148 </TD></TR></TABLE>
 149
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