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29 </h4></div></div></div>
30 <a name=
"reference_operator_template_spec"></a><pre class=
"programlisting"><span class=
"keyword">template
</span> <span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">T
</span><span class=
"special">></span>
31 <span class=
"keyword">class
</span> <span class=
"identifier">optional
</span><span class=
"special"><</span><span class=
"identifier">T
</span><span class=
"special">&></span> <span class=
"comment">// specilization for lvalue references
</span>
32 <span class=
"special">{
</span>
33 <span class=
"keyword">public
</span> <span class=
"special">:
</span>
35 <span class=
"keyword">typedef
</span> <span class=
"identifier">T
</span><span class=
"special">&</span> <span class=
"identifier">value_type
</span><span class=
"special">;
</span>
36 <span class=
"keyword">typedef
</span> <span class=
"identifier">T
</span><span class=
"special">&</span> <span class=
"identifier">reference_type
</span><span class=
"special">;
</span>
37 <span class=
"keyword">typedef
</span> <span class=
"identifier">T
</span><span class=
"special">&</span> <span class=
"identifier">reference_const_type
</span><span class=
"special">;
</span> <span class=
"comment">// no const propagation
</span>
38 <span class=
"keyword">typedef
</span> <span class=
"identifier">T
</span><span class=
"special">&</span> <span class=
"identifier">rval_reference_type
</span><span class=
"special">;
</span>
39 <span class=
"keyword">typedef
</span> <span class=
"identifier">T
</span><span class=
"special">*
</span> <span class=
"identifier">pointer_type
</span><span class=
"special">;
</span>
40 <span class=
"keyword">typedef
</span> <span class=
"identifier">T
</span><span class=
"special">*
</span> <span class=
"identifier">pointer_const_type
</span><span class=
"special">;
</span> <span class=
"comment">// no const propagation
</span>
42 <span class=
"identifier">optional
</span> <span class=
"special">()
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_default_ctor"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
44 <span class=
"identifier">optional
</span> <span class=
"special">(
</span> <span class=
"identifier">none_t
</span> <span class=
"special">)
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_default_ctor"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
46 <span class=
"keyword">template
</span><span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">R
</span><span class=
"special">></span> <span class=
"identifier">optional
</span><span class=
"special">(
</span><span class=
"identifier">R
</span><span class=
"special">&&</span> <span class=
"identifier">r
</span><span class=
"special">)
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_value_ctor"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
48 <span class=
"keyword">template
</span> <span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">R
</span><span class=
"special">></span> <span class=
"identifier">optional
</span><span class=
"special">(
</span><span class=
"keyword">bool
</span> <span class=
"identifier">cond
</span><span class=
"special">,
</span> <span class=
"identifier">R
</span><span class=
"special">&&</span> <span class=
"identifier">r
</span><span class=
"special">)
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_cond_value_ctor"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
50 <span class=
"identifier">optional
</span> <span class=
"special">(
</span> <span class=
"identifier">optional
</span> <span class=
"keyword">const
</span><span class=
"special">&</span> <span class=
"identifier">rhs
</span> <span class=
"special">)
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_copy_ctor"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
52 <span class=
"keyword">template
</span><span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">U
</span><span class=
"special">></span> <span class=
"keyword">explicit
</span> <span class=
"identifier">optional
</span> <span class=
"special">(
</span> <span class=
"identifier">optional
</span><span class=
"special"><</span><span class=
"identifier">U
</span><span class=
"special">&></span> <span class=
"keyword">const
</span><span class=
"special">&</span> <span class=
"identifier">rhs
</span> <span class=
"special">)
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_ctor_from_opt_U"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
54 <span class=
"identifier">optional
</span><span class=
"special">&</span> <span class=
"keyword">operator
</span> <span class=
"special">=
</span> <span class=
"special">(
</span> <span class=
"identifier">none_t
</span> <span class=
"special">)
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_assign_none_t"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
57 <span class=
"identifier">optional
</span><span class=
"special">&</span> <span class=
"keyword">operator
</span> <span class=
"special">=
</span> <span class=
"special">(
</span> <span class=
"identifier">optional
</span> <span class=
"keyword">const
</span><span class=
"special">&</span> <span class=
"identifier">rhs
</span> <span class=
"special">)
</span> <span class=
"keyword">noexcept
</span><span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_copy_assign"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
59 <span class=
"keyword">template
</span><span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">U
</span><span class=
"special">></span> <span class=
"identifier">optional
</span><span class=
"special">&</span> <span class=
"keyword">operator
</span> <span class=
"special">=
</span> <span class=
"special">(
</span> <span class=
"identifier">optional
</span><span class=
"special"><</span><span class=
"identifier">U
</span><span class=
"special">&></span> <span class=
"keyword">const
</span><span class=
"special">&</span> <span class=
"identifier">rhs
</span> <span class=
"special">)
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_assign_optional_U"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
61 <span class=
"keyword">template
</span><span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">R
</span><span class=
"special">></span> <span class=
"identifier">optional
</span><span class=
"special">&</span> <span class=
"keyword">operator
</span> <span class=
"special">=
</span> <span class=
"special">(
</span><span class=
"identifier">R
</span><span class=
"special">&&</span> <span class=
"identifier">r
</span><span class=
"special">)
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_assign_R"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
63 <span class=
"keyword">template
</span><span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">R
</span><span class=
"special">></span> <span class=
"keyword">void
</span> <span class=
"identifier">emplace
</span> <span class=
"special">(
</span> <span class=
"identifier">R
</span><span class=
"special">&&</span> <span class=
"identifier">r
</span> <span class=
"special">)
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_emplace_R"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
65 <span class=
"identifier">T
</span><span class=
"special">&</span> <span class=
"identifier">get
</span><span class=
"special">()
</span> <span class=
"keyword">const
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_get"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
66 <span class=
"identifier">T
</span><span class=
"special">&</span> <span class=
"keyword">operator
</span> <span class=
"special">*()
</span> <span class=
"keyword">const
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_get"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
68 <span class=
"identifier">T
</span><span class=
"special">*
</span> <span class=
"keyword">operator
</span> <span class=
"special">-
>()
</span> <span class=
"keyword">const
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_arrow"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
70 <span class=
"identifier">T
</span><span class=
"special">&</span> <span class=
"identifier">value
</span><span class=
"special">()
</span> <span class=
"keyword">const
</span><span class=
"special">&</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_value"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
72 <span class=
"keyword">template
</span><span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">R
</span><span class=
"special">></span> <span class=
"identifier">T
</span><span class=
"special">&</span> <span class=
"identifier">value_or
</span><span class=
"special">(
</span> <span class=
"identifier">R
</span> <span class=
"special">&&</span> <span class=
"identifier">r
</span> <span class=
"special">)
</span> <span class=
"keyword">const
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_value_or"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
74 <span class=
"keyword">template
</span><span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">F
</span><span class=
"special">></span> <span class=
"identifier">T
</span><span class=
"special">&</span> <span class=
"identifier">value_or_eval
</span><span class=
"special">(
</span> <span class=
"identifier">F
</span> <span class=
"identifier">f
</span> <span class=
"special">)
</span> <span class=
"keyword">const
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_value_or_eval"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
76 <span class=
"identifier">T
</span><span class=
"special">*
</span> <span class=
"identifier">get_ptr
</span><span class=
"special">()
</span> <span class=
"keyword">const
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_get_ptr"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
78 <span class=
"keyword">explicit
</span> <span class=
"keyword">operator
</span> <span class=
"keyword">bool
</span><span class=
"special">()
</span> <span class=
"keyword">const
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_operator_bool"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
80 <span class=
"keyword">bool
</span> <span class=
"keyword">operator
</span><span class=
"special">!()
</span> <span class=
"keyword">const
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_operator_not"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
82 <span class=
"comment">// deprecated methods
</span>
84 <span class=
"comment">// (deprecated)
</span>
85 <span class=
"keyword">void
</span> <span class=
"identifier">reset
</span><span class=
"special">()
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_reset"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
87 <span class=
"comment">// (deprecated)
</span>
88 <span class=
"keyword">template
</span><span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">R
</span><span class=
"special">></span> <span class=
"keyword">void
</span> <span class=
"identifier">reset
</span> <span class=
"special">(
</span> <span class=
"identifier">R
</span> <span class=
"special">&&</span> <span class=
"identifier">r
</span> <span class=
"special">)
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_reset_value"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
90 <span class=
"comment">// (deprecated)
</span>
91 <span class=
"keyword">bool
</span> <span class=
"identifier">is_initialized
</span><span class=
"special">()
</span> <span class=
"keyword">const
</span> <span class=
"keyword">noexcept
</span> <span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_is_initialized"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
93 <span class=
"comment">// (deprecated)
</span>
94 <span class=
"keyword">template
</span><span class=
"special"><</span><span class=
"keyword">class
</span> <span class=
"identifier">R
</span><span class=
"special">></span> <span class=
"identifier">T
</span><span class=
"special">&</span> <span class=
"identifier">get_value_or
</span><span class=
"special">(
</span> <span class=
"identifier">R
</span> <span class=
"special">&&</span> <span class=
"identifier">r
</span> <span class=
"special">)
</span> <span class=
"identifier">constnoexcept
</span><span class=
"special">;
</span> <a class=
"link" href=
"detailed_semantics___optional_references.html#reference_optional_ref_get_value_or_value"><span class=
"inlinemediaobject"><img src=
"../../../images/callouts/R.png" alt=
"R"></span></a>
96 <span class=
"keyword">private
</span><span class=
"special">:
</span>
97 <span class=
"identifier">T
</span><span class=
"special">*
</span> <span class=
"identifier">ref
</span><span class=
"special">;
</span> <span class=
"comment">// exposition only
</span>
98 <span class=
"special">};
</span>
101 <table xmlns:
rev=
"http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width=
"100%"><tr>
102 <td align=
"left"></td>
103 <td align=
"right"><div class=
"copyright-footer">Copyright
© 2003-
2007 Fernando Luis Cacciola Carballal
<br>Copyright
© 2014-
2016 Andrzej Krzemie
ński
<p>
104 Distributed under the Boost Software License, Version
1.0. (See accompanying
105 file LICENSE_1_0.txt or copy at
<a href=
"http://www.boost.org/LICENSE_1_0.txt" target=
"_top">http://www.boost.org/LICENSE_1_0.txt
</a>)
110 <div class=
"spirit-nav">
111 <a accesskey=
"p" href=
"header_optional_optional_values.html"><img src=
"../../../../../../../doc/src/images/prev.png" alt=
"Prev"></a><a accesskey=
"u" href=
"../../../optional/reference/header__boost_optional_optional_hpp_.html"><img src=
"../../../../../../../doc/src/images/up.png" alt=
"Up"></a><a accesskey=
"h" href=
"../../../index.html"><img src=
"../../../../../../../doc/src/images/home.png" alt=
"Home"></a><a accesskey=
"n" href=
"detailed_semantics___optional_values.html"><img src=
"../../../../../../../doc/src/images/next.png" alt=
"Next"></a>