46 lines
1.6 KiB
Plaintext
46 lines
1.6 KiB
Plaintext
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[/==============================================================================
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Copyright (C) 2001-2010 Joel de Guzman
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Copyright (C) 2001-2005 Dan Marsden
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Copyright (C) 2001-2010 Thomas Heller
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Distributed under the Boost Software License, Version 1.0. (See accompanying
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file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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===============================================================================/]
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[section Actor]
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The `Actor` is the main concept behind the library. Actors are function objects.
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An actor can accept 0 to `BOOST_PHOENIX_LIMIT` arguments.
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[note You can set `BOOST_PHOENIX_LIMIT`, the predefined maximum arity an
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actor can take. By default, `BOOST_PHOENIX_LIMIT` is set to 10.]
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Phoenix supplies an `actor` class template whose specializations
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model the `Actor` concept. `actor` has one template parameter, `Expr`,
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that supplies the underlying expression to evaluate.
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template <typename Expr>
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struct actor
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{
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return_type
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operator()() const;
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template <typename T0>
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return_type
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operator()(T0& _0) const;
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template <typename T0, typename T1>
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return_type
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operator()(T0& _0, T1& _1) const;
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//...
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};
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The actor class accepts the arguments through a set of function call operators
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for 0 to `BOOST_PHOENIX_LIMIT` arities (Don't worry about the details, for now. Note, for example,
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that we skimp over the details regarding `return_type`). The arguments are passed through to
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the evaluation mechanism. For more information see [link phoenix.inside.actor Inside Actors].
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[endsect]
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