boost-react-native-bundle

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">    <html> <head> <meta name="generator" content= "HTML Tidy for Windows (vers 1st August 2002), see www.w3.org"> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <link rel="stylesheet" type="text/css" href="../boost.css"> <title>Boost.Python - <boost/python/operators.hpp></title> </head> <body> <table border="0" cellpadding="7" cellspacing="0" width="100%" summary= "header"> <tr> <td valign="top" width="300"> <h3><a href="../../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../../boost.png" border="0"></a></h3> </td> <td valign="top"> <h1 align="center"><a href="../index.html">Boost.Python</a></h1> <h2 align="center">Header <boost/python/operators.hpp></h2> </td> </tr> </table> <hr> <h2>Contents</h2> <dl class="page-index"> <dt><a href="#introduction">Introduction</a></dt> <dt><a href="#classes">Classes</a></dt> <dd> <dl class="page-index"> <dt><a href="#self_t-spec">Class <code>self_ns::self_t</code></a></dt> <dd> <dl class="page-index"> <dt><a href="#self_t-spec-synopsis">Class <code>self_t</code> synopsis</a></dt> <dt><a href="#self_t-spec-inplace">Class <code>self_t</code> inplace operators</a></dt> <dt><a href="#self_t-spec-comparisons">Class <code>self_t</code> comparison functions</a></dt> <dt><a href="#self_t-spec-ops">Class <code>self_t</code> non-member operations</a></dt> <dt><a href="#self_t-spec-value-unary-ops">Class <code>self_t</code> unary operations</a></dt> <dt><a href="#self_t-spec-value-ops">Class <code>self_t</code> value operations</a></dt> </dl> </dd> <dt><a href="#other-spec">Class template <code>other</code></a></dt> <dd> <dl class="page-index"> <dt><a href="#other-spec-synopsis">Class <code>other</code> synopsis</a></dt> </dl> </dd> <dt><a href="#operator_-spec">Class template <code>operator_</code></a></dt> <dd> <dl class="page-index"> <dt><a href="#operator_-spec-synopsis">Class <code>operator_</code> synopsis</a></dt> </dl> </dd> </dl> </dd> <dt><a href="#objects">Objects</a></dt> <dd> <dl class="page-index"> <dt><a href="#self-spec">self</a></dt> </dl> </dd> <dt><a href="#examples">Examples</a></dt> </dl> <hr> <h2><a name="introduction"></a>Introduction</h2> <p><code><boost/python/operators.hpp></code> provides types and functions for automatically generating Python <a href= "http://www.python.org/doc/ref/specialnames.html">special methods</a> from the corresponding C++ constructs. Most of these constructs are operator expressions, hence the name. To use the facility, substitute the <code><a href="#self-spec">self</a></code> object for an object of the class type being wrapped in the expression to be exposed, and pass the result to <a href= "class.html#class_-spec-modifiers">class_<>::def()</a>. Much of what is exposed in this header should be considered part of the implementation, so is not documented in detail here.</p> <h2><a name="classes"></a>Classes</h2> <h3><a name="self_t-spec"></a>Class <code>self_ns::self_t</code></h3> <p><code>self_ns::self_t</code> is the actual type of the <a href= "#self-spec"><code>self</code></a> object. The library isolates <code>self_t</code> in its own namespace, <code>self_ns</code>, in order to prevent the generalized operator templates which operate on it from being found by argument-dependent lookup in other contexts. This should be considered an implementation detail, since users should never have to mention <code>self_t</code> directly.</p> <h4><a name="self_t-spec-synopsis"></a>Class <code>self_ns::self_t</code> synopsis</h4> <pre> namespace boost { namespace python { namespace self_ns { { <i>unspecified-type-declaration</i> self_t; // inplace operators template <class T> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator+=(self_t, T); template <class T> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator-=(self_t, T); template <class T> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator*=(self_t, T); template <class T> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator/=(self_t, T); template <class T> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator%=(self_t, T); template <class T> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator>>=(self_t, T); template <class T> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator<<=(self_t, T); template <class T> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator&=(self_t, T); template <class T> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator^=(self_t, T); template <class T> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator|=(self_t, T); // comparisons template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator==(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator!=(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator<(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator>(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator<=(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator>=(L const&, R const&); // non-member operations template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator+(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator-(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator*(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator/(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator%(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator>>(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator<<(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator&(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator^(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator|(L const&, R const&); template <class L, class R> <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> pow(L const&, R const&); // unary operations <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator-(self_t); <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator+(self_t); <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator~(self_t); <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> operator!(self_t); // value operations <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> int_(self_t); <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> long_(self_t); <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> float_(self_t); <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> complex_(self_t); <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> str(self_t); <a href= "#operator_-spec">operator_</a><<i>unspecified</i>> repr(self_t); }}}; </pre> The tables below describe the methods generated when the results of the expressions described are passed as arguments to <a href= "class.html#class_-spec-modifiers">class_<>::def()</a>. <code><b>x</b></code> is an object of the class type being wrapped. <h4><a name="self_t-spec-inplace"></a>Class <code>self_t</code> inplace operators</h4> In the table below, If <code><b>r</b></code> is an object of type <code><a href="#other-spec">other</a><T></code>, <code><b>y</b></code> is an object of type <code>T</code>; otherwise, <code><b>y</b></code> is an object of the same type as <code><b>r</b></code>. <table border="1" summary="self_t inplace operators"> <tr> <th>C++ Expression</th> <th>Python Method Name</th> <th>C++ Implementation</th> </tr> <tr> <td><code>self += r</code></td> <td><code>__iadd__</code></td> <td><code>x += y</code></td> </tr> <tr> <td><code>self -= r</code></td> <td><code>__isub__</code></td> <td><code>x -= y</code></td> </tr> <tr> <td><code>self *= r</code></td> <td><code>__imul__</code></td> <td><code>x *= y</code></td> </tr> <tr> <td><code>self /= r</code></td> <td><code>__idiv__</code></td> <td><code>x /= y</code></td> </tr> <tr> <td><code>self %= r</code></td> <td><code>__imod__</code></td> <td><code>x %= y</code></td> </tr> <tr> <td><code>self >>= r</code></td> <td><code>__irshift__</code></td> <td><code>x >>= y</code></td> </tr> <tr> <td><code>self <<= r</code></td> <td><code>__ilshift__</code></td> <td><code>x <<= y</code></td> </tr> <tr> <td><code>self &= r</code></td> <td><code>__iand__</code></td> <td><code>x &= y</code></td> </tr> <tr> <td><code>self ^= r</code></td> <td><code>__ixor__</code></td> <td><code>x ^= y</code></td> </tr> <tr> <td><code>self |= r</code></td> <td><code>__ior__</code></td> <td><code>x |= y</code></td> </tr> </table> <h4><a name="self_t-spec-comparisons"></a>Class <code>self_t</code> comparison functions</h4> In the tables below, if <code><b>r</b></code> is of type <code><a href= "#self_t-spec">self_t</a></code>, <code><b>y</b></code> is an object of the same type as <code>x</code>; <br> if <code><b>l</b></code> or <code><b>r</b></code> is an object of type <code><a href="#other-spec">other</a><T></code>, <code><b>y</b></code> is an object of type <code>T</code>; <br> otherwise, <code><b>y</b></code> is an object of the same type as <code><b>l</b></code> or <code><b>r</b></code>.<br> <code><b>l</b></code> is never of type <code><a href= "#self_t-spec">self_t</a></code>. <p>The column of <b>Python Expressions</b> illustrates the expressions that will be supported in Python for objects convertible to the types of <code>x</code> and <code>y</code>. The secondary operation arises due to Python's <a href= "http://www.python.org/doc/ref/customization.html#l2h-89">reflection rules</a> for rich comparison operators, and are only used when the corresponding operation is not defined as a method of the <code>y</code> object.</p> <table border="1" summary="self_t comparison functions"> <tr> <th>C++ Expression</th> <th>Python Method Name</th> <th>C++ Implementation</th> <th>Python Expressions<br> (primary, secondary)</th> </tr> <tr> <td><code>self == r</code></td> <td><code>__eq__</code></td> <td><code>x == y</code></td> <td><code>x == y, y == x</code></td> </tr> <tr> <td><code>l == self</code></td> <td><code>__eq__</code></td> <td><code>y == x</code></td> <td><code>y == x, x == y</code></td> </tr> <tr> <td><code>self != r</code></td> <td><code>__ne__</code></td> <td><code>x != y</code></td> <td><code>x != y, y != x</code></td> </tr> <tr> <td><code>l != self</code></td> <td><code>__ne__</code></td> <td><code>y != x</code></td> <td><code>y != x, x != y</code></td> </tr> <tr> <td><code>self < r</code></td> <td><code>__lt__</code></td> <td><code>x < y</code></td> <td><code>x < y, y > x</code></td> </tr> <tr> <td><code>l < self</code></td> <td><code>__gt__</code></td> <td><code>y < x</code></td> <td><code>y > x, x < y</code></td> </tr> <tr> <td><code>self > r</code></td> <td><code>__gt__</code></td> <td><code>x > y</code></td> <td><code>x > y, y < x</code></td> </tr> <tr> <td><code>l > self</code></td> <td><code>__lt__</code></td> <td><code>y > x</code></td> <td><code>y < x, x > y</code></td> </tr> <tr> <td><code>self <= r</code></td> <td><code>__le__</code></td> <td><code>x <= y</code></td> <td><code>x <= y, y >= x</code></td> </tr> <tr> <td><code>l <= self</code></td> <td><code>__ge__</code></td> <td><code>y <= x</code></td> <td><code>y >= x, x <= y</code></td> </tr> <tr> <td><code>self >= r</code></td> <td><code>__ge__</code></td> <td><code>x >= y</code></td> <td><code>x >= y, y <= x</code></td> </tr> <tr> <td><code>l >= self</code></td> <td><code>__le__</code></td> <td><code>y >= x</code></td> <td><code>y <= x, x >= y</code></td> </tr> </table> <h4><a name="self_t-spec-ops"></a>Class <code>self_t</code> non-member operations</h4> The operations whose names begin with "<code>__r</code>" below will only be called if the left-hand operand does not already support the given operation, as described <a href= "http://www.python.org/doc/current/ref/numeric-types.html#l2h-152">here</a>. <table border="1" summary="self_t non-member operations"> <tr> <th>C++ Expression</th> <th>Python Method Name</th> <th>C++ Implementation</th> </tr> <tr> <td><code>self + r</code></td> <td><code>__add__</code></td> <td><code>x + y</code></td> </tr> <tr> <td><code>l + self</code></td> <td><code>__radd__</code></td> <td><code>y + x</code></td> </tr> <tr> <td><code>self - r</code></td> <td><code>__sub__</code></td> <td><code>x - y</code></td> </tr> <tr> <td><code>l - self</code></td> <td><code>__rsub__</code></td> <td><code>y - x</code></td> </tr> <tr> <td><code>self * r</code></td> <td><code>__mul__</code></td> <td><code>x * y</code></td> </tr> <tr> <td><code>l * self</code></td> <td><code>__rmul__</code></td> <td><code>y * x</code></td> </tr> <tr> <td><code>self / r</code></td> <td><code>__div__</code></td> <td><code>x / y</code></td> </tr> <tr> <td><code>l / self</code></td> <td><code>__rdiv__</code></td> <td><code>y / x</code></td> </tr> <tr> <td><code>self % r</code></td> <td><code>__mod__</code></td> <td><code>x % y</code></td> </tr> <tr> <td><code>l % self</code></td> <td><code>__rmod__</code></td> <td><code>y % x</code></td> </tr> <tr> <td><code>self >> r</code></td> <td><code>__rshift__</code></td> <td><code>x >> y</code></td> </tr> <tr> <td><code>l >> self</code></td> <td><code>__rrshift__</code></td> <td><code>y >> x</code></td> </tr> <tr> <td><code>self << r</code></td> <td><code>__lshift__</code></td> <td><code>x << y</code></td> </tr> <tr> <td><code>l << self</code></td> <td><code>__rlshift__</code></td> <td><code>y << x</code></td> </tr> <tr> <td><code>self & r</code></td> <td><code>__and__</code></td> <td><code>x & y</code></td> </tr> <tr> <td><code>l & self</code></td> <td><code>__rand__</code></td> <td><code>y & x</code></td> </tr> <tr> <td><code>self ^ r</code></td> <td><code>__xor__</code></td> <td><code>x ^ y</code></td> </tr> <tr> <td><code>l ^ self</code></td> <td><code>__rxor__</code></td> <td><code>y ^ x</code></td> </tr> <tr> <td><code>self | r</code></td> <td><code>__or__</code></td> <td><code>x | y</code></td> </tr> <tr> <td><code>l | self</code></td> <td><code>__ror__</code></td> <td><code>y | x</code></td> </tr> <tr> <td><code>pow(self, r)</code></td> <td><code>__pow__</code></td> <td><code>pow(x, y)</code></td> </tr> <tr> <td><code>pow(l, self)</code></td> <td><code>__rpow__</code></td> <td><code>pow(y, x)</code></td> </tr> </table> <h4><a name="self_t-spec-value-unary-ops"></a>Class <code>self_t</code> unary operations</h4> <table border="1" summary="self_t unary operations"> <tr> <th>C++ Expression</th> <th>Python Method Name</th> <th>C++ Implementation</th> </tr> <tr> <td><code>-self</code></td> <td><code>__neg__</code></td> <td><code>-x</code></td> </tr> <tr> <td><code>+self</code></td> <td><code>__pos__</code></td> <td><code>+x</code></td> </tr> <tr> <td><code>~self</code></td> <td><code>__invert__</code></td> <td><code>~x</code></td> </tr> <tr> <td><code>not self</code><br><i>or</i><br><code>!self</code></td> <td><code>__nonzero__</code></td> <td><code>!!x</code></td> </tr> </table> <h4><a name="self_t-spec-value-ops"></a>Class <code>self_t</code> value operations</h4> <table border="1" summary="self_t value operations"> <tr> <th>C++ Expression</th> <th>Python Method Name</th> <th>C++ Implementation</th> </tr> <tr> <td><code>int_(self)</code></td> <td><code>__int__</code></td> <td><code>long(x)</code></td> </tr> <tr> <td><code>long_</code></td> <td><code>__long__</code></td> <td><code>PyLong_FromLong(x)</code></td> </tr> <tr> <td><code>float_</code></td> <td><code>__float__</code></td> <td><code>double(x)</code></td> </tr> <tr> <td><code>complex_</code></td> <td><code>__complex__</code></td> <td><code>std::complex<double>(x)</code></td> </tr> <tr> <td><code>str</code></td> <td><code>__str__</code></td> <td><code><a href= "../../../conversion/lexical_cast.htm#lexical_cast">lexical_cast</a><std::string>(x)</code></td> </tr> <tr> <td><code>repr</code></td> <td><code>__repr__</code></td> <td><code><a href= "../../../conversion/lexical_cast.htm#lexical_cast">lexical_cast</a><std::string>(x)</code></td> </tr> </table> <h3><a name="other-spec"></a>Class Template <code>other</code></h3> <p>Instances of <code>other<T></code> can be used in operator expressions with <a href="#self-spec">self</a>; the result is equivalent to the same expression with a <code>T</code> object in place of <code>other<T></code>. Use <code>other<T></code> to prevent construction of a <code>T</code> object in case it is heavyweight, when no constructor is available, or simply for clarity.</p> <h4><a name="other-spec-synopsis"></a>Class Template other synopsis</h4> <pre> namespace boost { namespace python { template <class T> struct other { }; }} </pre>  <h3><a name="operator_-spec"></a>Class Template <code>detail::operator_</code></h3> <p>Instantiations of <code>detail::operator_<></code> are used as the return type of operator expressions involving <code><a href= "#self-spec">self</a></code>. This should be considered an implementation detail and is only documented here as a way of showing how the result of <code>self</code>-expressions match calls to <a href= "class.html#class_-spec-modifiers">class_<>::def()</a>.</p> <h4><a name="operator_-spec-synopsis"></a>Class Template <code>detail::operator_</code> synopsis</h4> <pre> namespace boost { namespace python { namespace detail { template <<i>unspecified</i>> struct operator_ { }; }}} </pre> <h2><a name="objects"></a>Objects</h2> <p><a name="self-spec"><code>self</code></a></p> <pre> namespace boost { namespace python { using self_ns::self; }} </pre> <h2><a name="examples"></a>Example</h2> <pre> #include <boost/python/module.hpp> #include <boost/python/class.hpp> #include <boost/python/operators.hpp> #include <boost/operators.hpp> struct number : boost::<a href= "../../../utility/operators.htm#grpd_oprs">integer_arithmetic</a><number> { explicit number(long x_) : x(x_) {} operator long() const { return x; } template <class T> number& operator+=(T const& rhs) { x += rhs; return *this; } template <class T> number& operator-=(T const& rhs) { x -= rhs; return *this; } template <class T> number& operator*=(T const& rhs) { x *= rhs; return *this; } template <class T> number& operator/=(T const& rhs) { x /= rhs; return *this; } template <class T> number& operator%=(T const& rhs) { x %= rhs; return *this; } long x; }; using namespace boost::python; BOOST_PYTHON_MODULE(demo) { class_<number>("number", init<long>()) // interoperate with self .def(self += self) .def(self + self) .def(self -= self) .def(self - self) .def(self *= self) .def(self * self) .def(self /= self) .def(self / self) .def(self %= self) .def(self % self) // Convert to Python int .def(int_(self)) // interoperate with long .def(self += long()) .def(self + long()) .def(long() + self) .def(self -= long()) .def(self - long()) .def(long() - self) .def(self *= long()) .def(self * long()) .def(long() * self) .def(self /= long()) .def(self / long()) .def(long() / self) .def(self %= long()) .def(self % long()) .def(long() % self) ; } </pre> <p>Revised  5 October, 2004  </p> <p><i>© Copyright <a href= "http://www.boost.org/people/dave_abrahams.htm">Dave Abrahams</a> 2002.</i></p> </body> </html>