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