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- <div class="section">
- <div class="titlepage"><div><div><h2 class="title" style="clear: both">
- <a name="boost_numericconversion.converter___function_object"></a><a class="link" href="converter___function_object.html" title="converter<> function object">converter<>
- function object</a>
- </h2></div></div></div>
- <div class="toc"><dl class="toc">
- <dt><span class="section"><a href="converter___function_object.html#boost_numericconversion.converter___function_object.synopsis">Synopsis</a></span></dt>
- <dt><span class="section"><a href="converter___function_object.html#boost_numericconversion.converter___function_object.template_parameters">Template
- parameters</a></span></dt>
- <dt><span class="section"><a href="converter___function_object.html#boost_numericconversion.converter___function_object.member_functions">Member
- functions</a></span></dt>
- <dt><span class="section"><a href="converter___function_object.html#boost_numericconversion.converter___function_object.range_checking_logic">Range
- Checking Logic</a></span></dt>
- <dt><span class="section"><a href="converter___function_object.html#boost_numericconversion.converter___function_object.examples">Examples</a></span></dt>
- </dl></div>
- <div class="section">
- <div class="titlepage"><div><div><h3 class="title">
- <a name="boost_numericconversion.converter___function_object.synopsis"></a><a class="link" href="converter___function_object.html#boost_numericconversion.converter___function_object.synopsis" title="Synopsis">Synopsis</a>
- </h3></div></div></div>
- <pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">numeric</span> <span class="special">{</span>
- <span class="keyword">template</span><span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span>
- <span class="keyword">class</span> <span class="identifier">S</span><span class="special">,</span>
- <span class="keyword">class</span> <span class="identifier">Traits</span><span class="special">,</span> <span class="special">=</span> <span class="identifier">conversion_traits</span><span class="special"><</span><span class="identifier">T</span><span class="special">,</span><span class="identifier">S</span><span class="special">></span>
- <span class="keyword">class</span> <span class="identifier">OverflowHandler</span> <span class="special">=</span> <span class="identifier">def_overflow_handler</span><span class="special">,</span>
- <span class="keyword">class</span> <span class="identifier">Float2IntRounder</span> <span class="special">=</span> <span class="identifier">Trunc</span><span class="special"><</span> <span class="keyword">typename</span> <span class="identifier">Traits</span><span class="special">::</span><span class="identifier">source_type</span> <span class="special">>,</span>
- <span class="keyword">class</span> <span class="identifier">RawConverter</span> <span class="special">=</span> <span class="identifier">raw_converter</span><span class="special"><</span><span class="identifier">Traits</span><span class="special">>,</span>
- <span class="keyword">class</span> <span class="identifier">UserRangeChecker</span> <span class="special">=</span> <span class="identifier">UseInternalRangeChecker</span>
- <span class="special">></span>
- <span class="keyword">struct</span> <span class="identifier">converter</span>
- <span class="special">{</span>
- <span class="keyword">typedef</span> <span class="identifier">Traits</span> <span class="identifier">traits</span> <span class="special">;</span>
- <span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">Traits</span><span class="special">::</span><span class="identifier">source_type</span> <span class="identifier">source_type</span> <span class="special">;</span>
- <span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">Traits</span><span class="special">::</span><span class="identifier">argument_type</span> <span class="identifier">argument_type</span> <span class="special">;</span>
- <span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">Traits</span><span class="special">::</span><span class="identifier">result_type</span> <span class="identifier">result_type</span> <span class="special">;</span>
- <span class="keyword">static</span> <span class="identifier">result_type</span> <span class="identifier">convert</span> <span class="special">(</span> <span class="identifier">argument_type</span> <span class="identifier">s</span> <span class="special">)</span> <span class="special">;</span>
- <span class="identifier">result_type</span> <span class="keyword">operator</span><span class="special">()</span> <span class="special">(</span> <span class="identifier">argument_type</span> <span class="identifier">s</span> <span class="special">)</span> <span class="keyword">const</span> <span class="special">;</span>
- <span class="comment">// Internal member functions:</span>
- <span class="keyword">static</span> <span class="identifier">range_check_result</span> <span class="identifier">out_of_range</span> <span class="special">(</span> <span class="identifier">argument_type</span> <span class="identifier">s</span> <span class="special">)</span> <span class="special">;</span>
- <span class="keyword">static</span> <span class="keyword">void</span> <span class="identifier">validate_range</span> <span class="special">(</span> <span class="identifier">argument_type</span> <span class="identifier">s</span> <span class="special">)</span> <span class="special">;</span>
- <span class="keyword">static</span> <span class="identifier">result_type</span> <span class="identifier">low_level_convert</span> <span class="special">(</span> <span class="identifier">argument_type</span> <span class="identifier">s</span> <span class="special">)</span> <span class="special">;</span>
- <span class="keyword">static</span> <span class="identifier">source_type</span> <span class="identifier">nearbyint</span> <span class="special">(</span> <span class="identifier">argument_type</span> <span class="identifier">s</span> <span class="special">)</span> <span class="special">;</span>
- <span class="special">}</span> <span class="special">;</span>
- <span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace numeric, boost</span>
- </pre>
- <p>
- <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">converter</span><span class="special"><></span></code>
- is a <a href="http://www.sgi.com/tech/stl/UnaryFunction.html" target="_top">Unary Function
- Object</a> encapsulating the code to perform a numeric conversion with
- the direction and properties specified by the Traits template parameter.
- It can optionally take some <a class="link" href="numeric_converter_policy_classes.html" title="Numeric Converter Policy Classes">policies</a>
- which can be used to customize its behavior. The <code class="computeroutput"><span class="identifier">Traits</span></code>
- parameter is not a policy but the parameter that defines the conversion.
- </p>
- </div>
- <div class="section">
- <div class="titlepage"><div><div><h3 class="title">
- <a name="boost_numericconversion.converter___function_object.template_parameters"></a><a class="link" href="converter___function_object.html#boost_numericconversion.converter___function_object.template_parameters" title="Template parameters">Template
- parameters</a>
- </h3></div></div></div>
- <div class="informaltable"><table class="table">
- <colgroup>
- <col>
- <col>
- </colgroup>
- <thead><tr>
- <th>
- </th>
- <th>
- </th>
- </tr></thead>
- <tbody>
- <tr>
- <td>
- <p>
- <code class="computeroutput"><span class="identifier">T</span></code>
- </p>
- </td>
- <td>
- <p>
- The <a class="link" href="definitions.html#boost_numericconversion.definitions.numeric_types" title="Numeric Types">Numeric
- Type</a> which is the <span class="emphasis"><em>Target</em></span> of the conversion.
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <code class="computeroutput"><span class="identifier">S</span></code>
- </p>
- </td>
- <td>
- <p>
- The <a class="link" href="definitions.html#boost_numericconversion.definitions.numeric_types" title="Numeric Types">Numeric
- Type</a> which is the <span class="emphasis"><em>Source</em></span> of the conversion.
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <code class="computeroutput"><span class="identifier">Traits</span></code>
- </p>
- </td>
- <td>
- <p>
- This must be a conversion traits class with the interface of <a class="link" href="conversion_traits___traits_class.html" title="conversion_traits<> traits class"><code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">conversion_traits</span></code></a>
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <code class="computeroutput"><span class="identifier">OverflowHandler</span></code>
- </p>
- </td>
- <td>
- <p>
- <span class="bold"><strong>Stateless Policy</strong></span> called to administrate
- the result of the range checking.
- </p>
- <p>
- It is a <span class="bold"><strong>Function Object</strong></span> which
- receives the result of <code class="computeroutput"><span class="identifier">out_of_range</span><span class="special">()</span></code> and is called inside the <code class="computeroutput"><span class="identifier">validate_range</span><span class="special">()</span></code>
- static member function exposed by the converter.
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <code class="computeroutput"><span class="identifier">Float2IntRounder</span></code>
- </p>
- </td>
- <td>
- <p>
- <span class="bold"><strong>Stateless Policy</strong></span> which specifies
- the rounding mode used for float to integral conversions.
- </p>
- <p>
- It supplies the <code class="computeroutput"><span class="identifier">nearbyint</span><span class="special">()</span></code> static member function exposed
- by the converter.
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <code class="computeroutput"><span class="identifier">RawConverter</span></code>
- </p>
- </td>
- <td>
- <p>
- <span class="bold"><strong>Stateless Policy</strong></span> which is used
- to perform the actual conversion.
- </p>
- <p>
- It supplies the <code class="computeroutput"><span class="identifier">low_level_convert</span><span class="special">()</span></code> static member function exposed
- by the converter.
- </p>
- </td>
- </tr>
- <tr>
- <td>
- <p>
- <code class="computeroutput"><span class="identifier">UserRangeChecker</span></code>
- </p>
- </td>
- <td>
- <p>
- <span class="emphasis"><em>Special and Optional</em></span> <span class="bold"><strong>Stateless
- Policy</strong></span> which can be used to override the internal range
- checking logic.
- </p>
- <p>
- If given, supplies alternative code for the <code class="computeroutput"><span class="identifier">out_of_range</span><span class="special">()</span></code> and <code class="computeroutput"><span class="identifier">validate_range</span><span class="special">()</span></code> static member functions exposed
- by the converter.
- </p>
- </td>
- </tr>
- </tbody>
- </table></div>
- </div>
- <div class="section">
- <div class="titlepage"><div><div><h3 class="title">
- <a name="boost_numericconversion.converter___function_object.member_functions"></a><a class="link" href="converter___function_object.html#boost_numericconversion.converter___function_object.member_functions" title="Member functions">Member
- functions</a>
- </h3></div></div></div>
- <div class="blockquote"><blockquote class="blockquote"><p>
- <code class="computeroutput"><span class="keyword">static</span> <span class="identifier">result_type</span>
- <span class="identifier">converter</span><span class="special"><>::</span><span class="identifier">convert</span> <span class="special">(</span> <span class="identifier">argument_type</span> <span class="identifier">s</span>
- <span class="special">)</span> <span class="special">;</span> <span class="comment">// throw</span> </code>
- </p></blockquote></div>
- <p>
- This static member function converts an rvalue of type <code class="computeroutput"><span class="identifier">source_type</span></code>
- to an rvalue of type <code class="computeroutput"><span class="identifier">target_type</span></code>.
- </p>
- <p>
- If the conversion requires it, it performs a range checking before the conversion
- and passes the result of the check to the overflow handler policy (the default
- policy throws an exception if out-of-range is detected)
- </p>
- <p>
- The implementation of this function is actually built from the policies and
- is basically as follows:
- </p>
- <pre class="programlisting"><span class="identifier">result_type</span> <span class="identifier">converter</span><span class="special"><>::</span><span class="identifier">convert</span> <span class="special">(</span> <span class="identifier">argument_type</span> <span class="identifier">s</span> <span class="special">)</span>
- <span class="special">{</span>
- <span class="identifier">validate_range</span><span class="special">(</span><span class="identifier">s</span><span class="special">);</span> <span class="comment">// Implemented by the internal range checking logic</span>
- <span class="comment">// (which also calls the OverflowHandler policy)</span>
- <span class="comment">// or externally supplied by the UserRangeChecker policy.</span>
- <span class="identifier">s</span> <span class="special">=</span> <span class="identifier">nearbyint</span><span class="special">(</span><span class="identifier">s</span><span class="special">);</span> <span class="comment">// Externally supplied by the Float2IntRounder policy.</span>
- <span class="comment">// NOTE: This is actually called only for float to int conversions.</span>
- <span class="keyword">return</span> <span class="identifier">low_level_convert</span><span class="special">(</span><span class="identifier">s</span><span class="special">);</span> <span class="comment">// Externally supplied by the RawConverter policy.</span>
- <span class="special">}</span>
- </pre>
- <p>
- <code class="computeroutput"><span class="identifier">converter</span><span class="special"><>::</span><span class="keyword">operator</span><span class="special">()</span> <span class="keyword">const</span></code> just calls <code class="computeroutput"><span class="identifier">convert</span><span class="special">()</span></code>
- </p>
- <p>
- <span class="inlinemediaobject"><img src="../images/space.png" alt="space"></span>
- </p>
- <div class="blockquote"><blockquote class="blockquote"><p>
- <code class="computeroutput"><span class="keyword">static</span> <span class="identifier">range_check_result</span>
- <span class="identifier">numeric_converter</span><span class="special"><>::</span><span class="identifier">out_of_range</span> <span class="special">(</span>
- <span class="identifier">argument_type</span> <span class="identifier">s</span>
- <span class="special">)</span> <span class="special">;</span></code>
- </p></blockquote></div>
- <p>
- This <a class="link" href="converter___function_object.html#numeric_conversion_converter_internal">internal</a>
- static member function determines if the value <code class="computeroutput"><span class="identifier">s</span></code>
- can be represented by the target type without overflow.
- </p>
- <p>
- It does not determine if the conversion is <span class="emphasis"><em>exact</em></span>; that
- is, it does not detect <span class="emphasis"><em>inexact</em></span> conversions, only <span class="emphasis"><em>out-of-range</em></span>
- conversions (see the <a class="link" href="definitions.html#boost_numericconversion.definitions.exact__correctly_rounded_and_out_of_range_representations" title="Exact, Correctly Rounded and Out-Of-Range Representations">Definitions</a>
- for further details).
- </p>
- <p>
- The return value is of enum type <a class="link" href="numeric_converter_policy_classes.html#boost_numericconversion.numeric_converter_policy_classes.enum_range_check_result" title="enum range_check_result"><code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">range_check_result</span></code></a>
- </p>
- <p>
- The actual code for the range checking logic is optimized for the combined
- properties of the source and target types. For example, a non-subranged conversion
- (i.e: <code class="computeroutput"><span class="keyword">int</span></code>-><code class="computeroutput"><span class="keyword">float</span></code>), requires no range checking, so <code class="computeroutput"><span class="identifier">out_of_range</span><span class="special">()</span></code>
- returns <code class="computeroutput"><span class="identifier">cInRange</span></code> directly.
- See the following <a class="link" href="converter___function_object.html#boost_numericconversion.converter___function_object.range_checking_logic" title="Range Checking Logic">table</a>
- for more details.
- </p>
- <p>
- If the user supplied a <a class="link" href="numeric_converter_policy_classes.html#boost_numericconversion.numeric_converter_policy_classes.policy_userrangechecker" title="Policy UserRangeChecker">UserRangeChecker</a>
- policy, is this policy which implements this function, so the implementation
- is user defined, although it is expected to perform the same conceptual check
- and return the appropriate result.
- </p>
- <p>
- <span class="inlinemediaobject"><img src="../images/space.png" alt="space"></span>
- </p>
- <div class="blockquote"><blockquote class="blockquote"><p>
- <code class="computeroutput"><span class="keyword">static</span> <span class="keyword">void</span>
- <span class="identifier">numeric_converter</span><span class="special"><>::</span><span class="identifier">validate_range</span> <span class="special">(</span>
- <span class="identifier">argument_type</span> <span class="identifier">s</span>
- <span class="special">)</span> <span class="special">;</span> <span class="comment">// no throw</span> </code>
- </p></blockquote></div>
- <p>
- This <a class="link" href="converter___function_object.html#numeric_conversion_converter_internal">internal</a>
- static member function calls out_of_range(s), and passes the result to the
- <a class="link" href="numeric_converter_policy_classes.html#boost_numericconversion.numeric_converter_policy_classes.policy_overflowhandler" title="Policy OverflowHandler">OverflowHandler</a>
- policy class.
- </p>
- <p>
- For those Target/Source combinations which don't require range checking,
- this is an empty inline function.
- </p>
- <p>
- If the user supplied a <a class="link" href="numeric_converter_policy_classes.html#boost_numericconversion.numeric_converter_policy_classes.policy_userrangechecker" title="Policy UserRangeChecker">UserRangeChecker</a>
- policy, is this policy which implements this function, so the implementation
- is user defined, although it is expected to perform the same action as the
- default. In particular, it is expected to pass the result of the check to
- the overflow handler.
- </p>
- <p>
- <span class="inlinemediaobject"><img src="../images/space.png" alt="space"></span>
- </p>
- <div class="blockquote"><blockquote class="blockquote"><p>
- <code class="computeroutput"><span class="keyword">static</span> <span class="identifier">result_type</span>
- <span class="identifier">numeric_converter</span><span class="special"><>::</span><span class="identifier">low_level_convert</span> <span class="special">(</span>
- <span class="identifier">argument_type</span> <span class="identifier">s</span>
- <span class="special">)</span> <span class="special">;</span></code>
- </p></blockquote></div>
- <p>
- This <a class="link" href="converter___function_object.html#numeric_conversion_converter_internal">internal</a>
- static member function performs the actual conversion.
- </p>
- <p>
- This function is externally supplied by the <a class="link" href="numeric_converter_policy_classes.html#boost_numericconversion.numeric_converter_policy_classes.policy_rawconverter" title="Policy RawConverter">RawConverter</a>
- policy class.
- </p>
- <p>
- <span class="inlinemediaobject"><img src="../images/space.png" alt="space"></span>
- </p>
- <div class="blockquote"><blockquote class="blockquote"><p>
- <code class="computeroutput"><span class="keyword">static</span> <span class="identifier">source_type</span>
- <span class="identifier">converter</span><span class="special"><>::</span><span class="identifier">nearbyint</span> <span class="special">(</span>
- <span class="identifier">argument_type</span> <span class="identifier">s</span>
- <span class="special">)</span> <span class="special">;</span></code>
- </p></blockquote></div>
- <p>
- This <a class="link" href="converter___function_object.html#numeric_conversion_converter_internal">internal</a>
- static member function, which is <span class="underline">only used</span>
- for <code class="computeroutput"><span class="keyword">float</span></code> to <code class="computeroutput"><span class="keyword">int</span></code>
- conversions, returns an <span class="emphasis"><em>integer</em></span> value of <span class="emphasis"><em><span class="underline">floating-point type</span></em></span> according to some
- rounding direction.
- </p>
- <p>
- This function is externally supplied by the <a class="link" href="numeric_converter_policy_classes.html#boost_numericconversion.numeric_converter_policy_classes.policy_float2introunder" title="Policy Float2IntRounder">Float2IntRounder</a>
- policy class which encapsulates the specific rounding mode.
- </p>
- <p>
- <span class="inlinemediaobject"><img src="../images/space.png" alt="space"></span>
- </p>
- <a name="numeric_conversion_converter_internal"></a><h5>
- <a name="boost_numericconversion.converter___function_object.member_functions.h0"></a>
- <span class="phrase"><a name="boost_numericconversion.converter___function_object.member_functions.internal_member_functions"></a></span><a class="link" href="converter___function_object.html#boost_numericconversion.converter___function_object.member_functions.internal_member_functions">Internal
- Member Functions</a>
- </h5>
- <p>
- These static member functions build the actual conversion code used by <code class="computeroutput"><span class="identifier">convert</span><span class="special">()</span></code>.
- The user does not have to call these if calling <code class="computeroutput"><span class="identifier">convert</span><span class="special">()</span></code>, since <code class="computeroutput"><span class="identifier">convert</span><span class="special">()</span></code> calls them infernally, but they can be
- called separately for specific needs.
- </p>
- </div>
- <div class="section">
- <div class="titlepage"><div><div><h3 class="title">
- <a name="boost_numericconversion.converter___function_object.range_checking_logic"></a><a class="link" href="converter___function_object.html#boost_numericconversion.converter___function_object.range_checking_logic" title="Range Checking Logic">Range
- Checking Logic</a>
- </h3></div></div></div>
- <p>
- The following table summarizes the internal range checking logic performed
- for each combination of the properties of Source and Target.
- </p>
- <p>
- LowestT/HighestT denotes the highest and lowest values of the Target type,
- respectively.
- </p>
- <p>
- <code class="computeroutput"><span class="identifier">S</span><span class="special">(</span><span class="identifier">n</span><span class="special">)</span></code> is short
- for <code class="computeroutput"><span class="keyword">static_cast</span><span class="special"><</span><span class="identifier">S</span><span class="special">>(</span><span class="identifier">n</span><span class="special">)</span></code> (<code class="computeroutput"><span class="identifier">S</span></code> denotes the Source type).
- </p>
- <p>
- <code class="computeroutput"><span class="identifier">NONE</span></code> indicates that for this
- case there is no range checking.
- </p>
- <pre class="programlisting"><code class="literal">
- int_to_int |--> sig_to_sig |--> subranged |--> ( s >= S(LowestT) ) && ( s <= S(HighestT) )
- | |--> not subranged |--> NONE
- |
- |--> unsig_to_unsig |--> subranged |--> ( s >= S(LowestT) ) && ( s <= S(HighestT) )
- | |--> not subranged |--> NONE
- |
- |--> sig_to_unsig |--> pos subranged |--> ( s >= S(0) ) && ( s <= S(HighestT) )
- | |--> not pos subranged |--> ( s >= S(0) )
- |
- |--> unsig_to_sig |--> subranged |--> ( s <= S(HighestT) )
- | |--> not subranged |--> NONE
- </code>
- <code class="literal">
- int_to_float |--> NONE
- </code>
- <code class="literal">
- float_to_int |--> round_to_zero |--> ( s > S(LowestT)-S(1) ) && ( s < S(HighestT)+S(1) )
- |--> round_to_even_nearest |--> ( s >= S(LowestT)-S(0.5) ) && ( s < S(HighestT)+S(0.5) )
- |--> round_to_infinity |--> ( s > S(LowestT)-S(1) ) && ( s <= S(HighestT) )
- |--> round_to_neg_infinity |--> ( s >= S(LowestT) ) && ( s < S(HighestT)+S(1) )
- </code>
- <code class="literal">
- float_to_float |--> subranged |--> ( s >= S(LowestT) ) && ( s <= S(HighestT) )
- |--> not subranged |--> NONE
- </code>
- </pre>
- </div>
- <div class="section">
- <div class="titlepage"><div><div><h3 class="title">
- <a name="boost_numericconversion.converter___function_object.examples"></a><a class="link" href="converter___function_object.html#boost_numericconversion.converter___function_object.examples" title="Examples">Examples</a>
- </h3></div></div></div>
- <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">cassert</span><span class="special">></span>
- <span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">numeric</span><span class="special">/</span><span class="identifier">conversion</span><span class="special">/</span><span class="identifier">converter</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
- <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span> <span class="special">{</span>
- <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">converter</span><span class="special"><</span><span class="keyword">int</span><span class="special">,</span><span class="keyword">double</span><span class="special">></span> <span class="identifier">Double2Int</span> <span class="special">;</span>
- <span class="keyword">int</span> <span class="identifier">x</span> <span class="special">=</span> <span class="identifier">Double2Int</span><span class="special">::</span><span class="identifier">convert</span><span class="special">(</span><span class="number">2.0</span><span class="special">);</span>
- <span class="identifier">assert</span> <span class="special">(</span> <span class="identifier">x</span> <span class="special">==</span> <span class="number">2</span> <span class="special">);</span>
- <span class="keyword">int</span> <span class="identifier">y</span> <span class="special">=</span> <span class="identifier">Double2Int</span><span class="special">()(</span><span class="number">3.14</span><span class="special">);</span> <span class="comment">// As a function object.</span>
- <span class="identifier">assert</span> <span class="special">(</span> <span class="identifier">y</span> <span class="special">==</span> <span class="number">3</span> <span class="special">)</span> <span class="special">;</span> <span class="comment">// The default rounding is trunc.</span>
- <span class="keyword">try</span>
- <span class="special">{</span>
- <span class="keyword">double</span> <span class="identifier">m</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">bounds</span><span class="special"><</span><span class="keyword">double</span><span class="special">>::</span><span class="identifier">highest</span><span class="special">();</span>
- <span class="keyword">int</span> <span class="identifier">z</span> <span class="special">=</span> <span class="identifier">Double2Int</span><span class="special">::</span><span class="identifier">convert</span><span class="special">(</span><span class="identifier">m</span><span class="special">);</span> <span class="comment">// By default throws positive_overflow()</span>
- <span class="special">}</span>
- <span class="keyword">catch</span> <span class="special">(</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">positive_overflow</span> <span class="keyword">const</span><span class="special">&</span> <span class="special">)</span>
- <span class="special">{</span>
- <span class="special">}</span>
- <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span>
- <span class="special">}</span>
- </pre>
- </div>
- </div>
- <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
- <td align="left"></td>
- <td align="right"><div class="copyright-footer">Copyright © 2004-2007 Fernando
- Luis Cacciola Carballal<p>
- Distributed under the Boost Software License, Version 1.0. (See accompanying
- 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>)
- </p>
- </div></td>
- </tr></table>
- <hr>
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