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/*=============================================================================
Wave: A Standard compliant C++ preprocessor
Copyright (c) 2001-2004 Hartmut Kaiser
http://spirit.sourceforge.net/
Use, modification and distribution is subject to 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)
See Copyright.txt for full acknowledgements.
=============================================================================*/
#if !defined(CPP_EXPRESSION_VALUE_HPP_452FE66D_8754_4107_AF1E_E42255A0C18A_INCLUDED)
#define CPP_EXPRESSION_VALUE_HPP_452FE66D_8754_4107_AF1E_E42255A0C18A_INCLUDED
#if defined (BOOST_SPIRIT_DEBUG)
#include <iostream>
#endif // defined(BOOST_SPIRIT_DEBUG)
///////////////////////////////////////////////////////////////////////////////
namespace wave {
namespace grammars {
namespace closures {
///////////////////////////////////////////////////////////////////////////////
//
// The closure_value class represents the closure type, which is used for the
// expression grammar.
//
// This class was introduced to allow the expression grammar to respect
// the numeric type of a numeric literal or expression result.
//
///////////////////////////////////////////////////////////////////////////////
class closure_value {
typedef unsigned long ulong_t;
public:
enum value_type {
is_int = 1,
is_uint = 2,
is_bool = 3
};
closure_value() : type(is_int) { value.i = 0; }
explicit closure_value(int i) : type(is_int) { value.i = i; }
explicit closure_value(unsigned int ui) : type(is_uint) { value.ui = ui; }
explicit closure_value(long i) : type(is_int) { value.i = i; }
explicit closure_value(ulong_t ui) : type(is_uint) { value.ui = ui; }
explicit closure_value(bool b) : type(is_bool) { value.b = b; }
value_type get_type() const { return type; }
// implicit conversion
operator int() const
{
switch (type) {
case is_uint: return value.ui;
case is_bool: return value.b ? 1 : 0;
case is_int: break;
}
return value.i;
}
operator unsigned int() const
{
switch (type) {
case is_uint: return value.ui;
case is_bool: return value.b ? 1 : 0;
case is_int: break;
}
return value.i;
}
operator long() const
{
switch (type) {
case is_uint: return value.ui;
case is_bool: return value.b ? 1 : 0;
case is_int: break;
}
return value.i;
}
operator ulong_t() const
{
switch (type) {
case is_uint: return value.ui;
case is_bool: return value.b ? 1 : 0;
case is_int: break;
}
return value.i;
}
operator bool() const
{
switch (type) {
case is_uint: return value.ui != 0;
case is_bool: return value.b;
case is_int: break;
}
return value.i != 0.0;
}
// assignment
closure_value &operator= (closure_value const &rhs)
{
switch (rhs.get_type()) {
case is_int:
value.i = long(rhs);
type = is_int;
break;
case is_uint:
value.ui = ulong_t(rhs);
type = is_uint;
break;
case is_bool:
value.b = bool(rhs);
type = is_bool;
break;
}
return *this;
}
closure_value &operator= (int rhs)
{
type = is_int;
value.i = rhs;
return *this;
}
closure_value &operator= (unsigned int rhs)
{
type = is_uint;
value.ui = rhs;
return *this;
}
closure_value &operator= (long rhs)
{
type = is_int;
value.i = rhs;
return *this;
}
closure_value &operator= (ulong_t rhs)
{
type = is_uint;
value.ui = rhs;
return *this;
}
closure_value &operator= (bool rhs)
{
type = is_bool;
value.b = rhs;
return *this;
}
// arithmetics
closure_value &operator+= (closure_value const &rhs)
{
switch (type) {
case is_int: value.i += long(rhs); break;
case is_uint: value.ui += ulong_t(rhs); break;
case is_bool:
value.i = value.b + bool(rhs);
type = is_int;
}
return *this;
}
closure_value &operator-= (closure_value const &rhs)
{
switch (type) {
case is_int: value.i -= long(rhs); break;
case is_uint: value.ui -= ulong_t(rhs); break;
case is_bool:
value.i = value.b - bool(rhs);
type = is_int;
}
return *this;
}
closure_value &operator*= (closure_value const &rhs)
{
switch (type) {
case is_int: value.i *= long(rhs); break;
case is_uint: value.ui *= ulong_t(rhs); break;
case is_bool:
value.i = value.b * bool(rhs);
type = is_int;
}
return *this;
}
closure_value &operator/= (closure_value const &rhs)
{
switch (type) {
case is_int: value.i /= long(rhs); break;
case is_uint: value.ui /= ulong_t(rhs); break;
case is_bool:
value.i = int(value.b) / int(bool(rhs));
type = is_int;
}
return *this;
}
friend closure_value
operator- (closure_value const &rhs)
{
switch (rhs.type) {
case is_int: return closure_value(-long(rhs));
case is_bool: return closure_value(!bool(rhs));
case is_uint: break;
}
return closure_value(-(int)ulong_t(rhs));
}
friend closure_value
operator! (closure_value const &rhs)
{
switch (rhs.type) {
case is_int: return closure_value(!long(rhs));
case is_bool: return closure_value(!bool(rhs));
case is_uint: break;
}
return closure_value(!ulong_t(rhs));
}
// comparison
friend closure_value
operator== (closure_value const &lhs, closure_value const &rhs)
{
bool cmp = false;
switch (lhs.type) {
case is_int: cmp = long(lhs) == long(rhs); break;
case is_uint: cmp = ulong_t(lhs) == ulong_t(rhs); break;
case is_bool: cmp = bool(lhs) == bool(rhs); break;
}
return closure_value(cmp);
}
friend closure_value
operator!= (closure_value const &lhs, closure_value const &rhs)
{
return closure_value(!bool(lhs == rhs));
}
friend closure_value
operator> (closure_value const &lhs, closure_value const &rhs)
{
bool cmp = false;
switch (lhs.type) {
case is_int: cmp = long(lhs) > long(rhs); break;
case is_uint: cmp = ulong_t(lhs) > ulong_t(rhs); break;
case is_bool: cmp = bool(lhs) > bool(rhs); break;
}
return closure_value(cmp);
}
friend closure_value
operator< (closure_value const &lhs, closure_value const &rhs)
{
bool cmp = false;
switch (lhs.type) {
case is_int: cmp = long(lhs) < long(rhs); break;
case is_uint: cmp = ulong_t(lhs) < ulong_t(rhs); break;
case is_bool: cmp = bool(lhs) < bool(rhs); break;
}
return closure_value(cmp);
}
friend closure_value
operator<= (closure_value const &lhs, closure_value const &rhs)
{
return closure_value(!bool(lhs > rhs));
}
friend closure_value
operator>= (closure_value const &lhs, closure_value const &rhs)
{
return closure_value(!bool(lhs < rhs));
}
friend closure_value
operator> (closure_value const &lhs, int const rhs)
{
bool cmp = false;
switch (lhs.type) {
case is_int: cmp = long(lhs) > rhs; break;
case is_uint: cmp = ulong_t(lhs) > ulong_t(rhs); break;
case is_bool: cmp = (int)bool(lhs) > rhs; break;
}
return closure_value(cmp);
}
friend closure_value
operator< (closure_value const &lhs, int const rhs)
{
bool cmp = false;
switch (lhs.type) {
case is_int: cmp = long(lhs) < rhs; break;
case is_uint: cmp = ulong_t(lhs) < ulong_t(rhs); break;
case is_bool: cmp = (int)bool(lhs) < rhs; break;
}
return closure_value(cmp);
}
#if defined (BOOST_SPIRIT_DEBUG)
friend std::ostream&
operator<< (std::ostream &o, closure_value const &val)
{
switch (val.type) {
case is_int: o << "int(" << long(val) << ")"; break;
case is_uint: o << "unsigned int(" << ulong_t(val) << ")"; break;
case is_bool: o << "bool(" << bool(val) << ")"; break;
}
return o;
}
#endif // defined(BOOST_SPIRIT_DEBUG)
private:
value_type type;
union {
long i;
ulong_t ui;
bool b;
} value;
};
///////////////////////////////////////////////////////////////////////////////
} // namespace closures
} // namespace grammars
} // namespace wave
#endif // !defined(CPP_EXPRESSION_VALUE_HPP_452FE66D_8754_4107_AF1E_E42255A0C18A_INCLUDED)
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