udkapi/com/sun/star/beans/Optional.idl

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  19 #ifndef __com_sun_star_beans_Optional_idl__
  20 #define __com_sun_star_beans_Optional_idl__
  21
  22 module com {  module sun {  module star {  module beans {
  23
  24 /**
  25    An optional value of a given type.
  26
  27    <p>This structure is used as the type of interface attributes corresponding
  28    to instances of com::sun::star::beans::Property that
  29    have the com::sun::star::beans::PropertyAttribute::MAYBEVOID.  It might
  30    also be useful in other situations, for example as the return type of an
  31    interface method.</p>
  32  */
  33 struct Optional<T> {
  34     /**
  35        Marks this structure instance as having an actual value.
  36      */
  37     boolean IsPresent;
  38
  39     /**
  40        The actual value of this structure instance.
  41
  42        <p>If no actual value is present, a producer of such a structure instance
  43        should leave this member defaulted, and a consumer of such a structure
  44        instance should ignore the specific value stored in this member.</p>
  45      */
  46     T Value;
  47 };
  48
  49 }; }; }; };
  50
  51 #endif
  52
  53 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */