boost/proto/debug.hpp
///////////////////////////////////////////////////////////////////////////////
/// \file debug.hpp
/// Utilities for debugging Proto expression trees
//
// Copyright 2008 Eric Niebler. 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)
#ifndef BOOST_PROTO_DEBUG_HPP_EAN_12_31_2006
#define BOOST_PROTO_DEBUG_HPP_EAN_12_31_2006
#include <iostream>
#include <boost/preprocessor/stringize.hpp>
#include <boost/core/ref.hpp>
#include <boost/core/typeinfo.hpp>
#include <boost/mpl/assert.hpp>
#include <boost/proto/proto_fwd.hpp>
#include <boost/proto/traits.hpp>
#include <boost/proto/matches.hpp>
#include <boost/proto/fusion.hpp>
#include <boost/fusion/algorithm/iteration/for_each.hpp>
namespace boost { namespace proto
{
namespace tagns_ { namespace tag
{
#define BOOST_PROTO_DEFINE_TAG_INSERTION(Tag) \
/** \brief INTERNAL ONLY */ \
inline std::ostream &operator <<(std::ostream &sout, Tag const &) \
{ \
return sout << BOOST_PP_STRINGIZE(Tag); \
} \
/**/
BOOST_PROTO_DEFINE_TAG_INSERTION(terminal)
BOOST_PROTO_DEFINE_TAG_INSERTION(unary_plus)
BOOST_PROTO_DEFINE_TAG_INSERTION(negate)
BOOST_PROTO_DEFINE_TAG_INSERTION(dereference)
BOOST_PROTO_DEFINE_TAG_INSERTION(complement)
BOOST_PROTO_DEFINE_TAG_INSERTION(address_of)
BOOST_PROTO_DEFINE_TAG_INSERTION(logical_not)
BOOST_PROTO_DEFINE_TAG_INSERTION(pre_inc)
BOOST_PROTO_DEFINE_TAG_INSERTION(pre_dec)
BOOST_PROTO_DEFINE_TAG_INSERTION(post_inc)
BOOST_PROTO_DEFINE_TAG_INSERTION(post_dec)
BOOST_PROTO_DEFINE_TAG_INSERTION(shift_left)
BOOST_PROTO_DEFINE_TAG_INSERTION(shift_right)
BOOST_PROTO_DEFINE_TAG_INSERTION(multiplies)
BOOST_PROTO_DEFINE_TAG_INSERTION(divides)
BOOST_PROTO_DEFINE_TAG_INSERTION(modulus)
BOOST_PROTO_DEFINE_TAG_INSERTION(plus)
BOOST_PROTO_DEFINE_TAG_INSERTION(minus)
BOOST_PROTO_DEFINE_TAG_INSERTION(less)
BOOST_PROTO_DEFINE_TAG_INSERTION(greater)
BOOST_PROTO_DEFINE_TAG_INSERTION(less_equal)
BOOST_PROTO_DEFINE_TAG_INSERTION(greater_equal)
BOOST_PROTO_DEFINE_TAG_INSERTION(equal_to)
BOOST_PROTO_DEFINE_TAG_INSERTION(not_equal_to)
BOOST_PROTO_DEFINE_TAG_INSERTION(logical_or)
BOOST_PROTO_DEFINE_TAG_INSERTION(logical_and)
BOOST_PROTO_DEFINE_TAG_INSERTION(bitwise_and)
BOOST_PROTO_DEFINE_TAG_INSERTION(bitwise_or)
BOOST_PROTO_DEFINE_TAG_INSERTION(bitwise_xor)
BOOST_PROTO_DEFINE_TAG_INSERTION(comma)
BOOST_PROTO_DEFINE_TAG_INSERTION(mem_ptr)
BOOST_PROTO_DEFINE_TAG_INSERTION(assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(shift_left_assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(shift_right_assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(multiplies_assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(divides_assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(modulus_assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(plus_assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(minus_assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(bitwise_and_assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(bitwise_or_assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(bitwise_xor_assign)
BOOST_PROTO_DEFINE_TAG_INSERTION(subscript)
BOOST_PROTO_DEFINE_TAG_INSERTION(member)
BOOST_PROTO_DEFINE_TAG_INSERTION(if_else_)
BOOST_PROTO_DEFINE_TAG_INSERTION(function)
#undef BOOST_PROTO_DEFINE_TAG_INSERTION
}}
namespace hidden_detail_
{
struct ostream_wrapper
{
ostream_wrapper(std::ostream &sout)
: sout_(sout)
{}
std::ostream &sout_;
private:
ostream_wrapper &operator =(ostream_wrapper const &);
};
struct named_any
{
template<typename T>
named_any(T const &)
: name_(BOOST_CORE_TYPEID(T).name())
{}
char const *name_;
};
inline std::ostream &operator <<(ostream_wrapper sout_wrap, named_any t)
{
return sout_wrap.sout_ << t.name_;
}
}
namespace detail
{
// copyable functor to pass by value to fusion::foreach
struct display_expr_impl;
struct display_expr_impl_functor
{
display_expr_impl_functor(display_expr_impl const& impl): impl_(impl)
{}
template<typename Expr>
void operator()(Expr const &expr) const
{
this->impl_(expr);
}
private:
display_expr_impl const& impl_;
};
struct display_expr_impl
{
explicit display_expr_impl(std::ostream &sout, int depth = 0)
: depth_(depth)
, first_(true)
, sout_(sout)
{}
template<typename Expr>
void operator()(Expr const &expr) const
{
this->impl(expr, mpl::long_<arity_of<Expr>::value>());
}
private:
display_expr_impl(display_expr_impl const &);
display_expr_impl &operator =(display_expr_impl const &);
template<typename Expr>
void impl(Expr const &expr, mpl::long_<0>) const
{
using namespace hidden_detail_;
typedef typename tag_of<Expr>::type tag;
this->sout_.width(this->depth_);
this->sout_ << (this->first_? "" : ", ");
this->sout_ << tag() << "(" << proto::value(expr) << ")\n";
this->first_ = false;
}
template<typename Expr, typename Arity>
void impl(Expr const &expr, Arity) const
{
using namespace hidden_detail_;
typedef typename tag_of<Expr>::type tag;
this->sout_.width(this->depth_);
this->sout_ << (this->first_? "" : ", ");
this->sout_ << tag() << "(\n";
display_expr_impl display(this->sout_, this->depth_ + 4);
fusion::for_each(expr, display_expr_impl_functor(display));
this->sout_.width(this->depth_);
this->sout_ << "" << ")\n";
this->first_ = false;
}
int depth_;
mutable bool first_;
std::ostream &sout_;
};
}
namespace functional
{
/// \brief Pretty-print a Proto expression tree.
///
/// A PolymorphicFunctionObject which accepts a Proto expression
/// tree and pretty-prints it to an \c ostream for debugging
/// purposes.
struct display_expr
{
BOOST_PROTO_CALLABLE()
typedef void result_type;
/// \param sout The \c ostream to which the expression tree
/// will be written.
/// \param depth The starting indentation depth for this node.
/// Children nodes will be displayed at a starting
/// depth of <tt>depth+4</tt>.
explicit display_expr(std::ostream &sout = std::cout, int depth = 0)
: depth_(depth)
, sout_(sout)
{}
/// \brief Pretty-print the current node in a Proto expression
/// tree.
template<typename Expr>
void operator()(Expr const &expr) const
{
detail::display_expr_impl(this->sout_, this->depth_)(expr);
}
private:
int depth_;
reference_wrapper<std::ostream> sout_;
};
}
/// \brief Pretty-print a Proto expression tree.
///
/// \note Equivalent to <tt>functional::display_expr(0, sout)(expr)</tt>
/// \param expr The Proto expression tree to pretty-print
/// \param sout The \c ostream to which the output should be
/// written. If not specified, defaults to
/// <tt>std::cout</tt>.
template<typename Expr>
void display_expr(Expr const &expr, std::ostream &sout)
{
functional::display_expr(sout, 0)(expr);
}
/// \overload
///
template<typename Expr>
void display_expr(Expr const &expr)
{
functional::display_expr()(expr);
}
/// \brief Assert at compile time that a particular expression
/// matches the specified grammar.
///
/// \note Equivalent to <tt>BOOST_MPL_ASSERT((proto::matches\<Expr, Grammar\>))</tt>
/// \param expr The Proto expression to check againts <tt>Grammar</tt>
template<typename Grammar, typename Expr>
void assert_matches(Expr const & /*expr*/)
{
BOOST_MPL_ASSERT((proto::matches<Expr, Grammar>));
}
/// \brief Assert at compile time that a particular expression
/// does not match the specified grammar.
///
/// \note Equivalent to <tt>BOOST_MPL_ASSERT_NOT((proto::matches\<Expr, Grammar\>))</tt>
/// \param expr The Proto expression to check againts <tt>Grammar</tt>
template<typename Grammar, typename Expr>
void assert_matches_not(Expr const & /*expr*/)
{
BOOST_MPL_ASSERT_NOT((proto::matches<Expr, Grammar>));
}
/// \brief Assert at compile time that a particular expression
/// matches the specified grammar.
///
/// \note Equivalent to <tt>proto::assert_matches\<Grammar\>(Expr)</tt>
/// \param Expr The Proto expression to check againts <tt>Grammar</tt>
/// \param Grammar The grammar used to validate Expr.
#define BOOST_PROTO_ASSERT_MATCHES(Expr, Grammar) \
(true ? (void)0 : boost::proto::assert_matches<Grammar>(Expr))
/// \brief Assert at compile time that a particular expression
/// does not match the specified grammar.
///
/// \note Equivalent to <tt>proto::assert_matches_not\<Grammar\>(Expr)</tt>
/// \param Expr The Proto expression to check againts <tt>Grammar</tt>
/// \param Grammar The grammar used to validate Expr.
#define BOOST_PROTO_ASSERT_MATCHES_NOT(Expr, Grammar) \
(true ? (void)0 : boost::proto::assert_matches_not<Grammar>(Expr))
}}
#endif