diff --git a/doc/Jamfile.v2 b/doc/Jamfile.v2
index 422ea5e..5088a46 100644
--- a/doc/Jamfile.v2
+++ b/doc/Jamfile.v2
@@ -1,3 +1,13 @@
+# Tribool library
+
+# Copyright (C) 2002-2003 Douglas Gregor
+
+# 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)
+
+# For more information, see http://www.boost.org/
+
project boost-sandbox/utility/doc ;
import boostbook ;
import doxygen ;
diff --git a/doc/tribool.boostbook b/doc/tribool.boostbook
index 1fa199a..80da397 100644
--- a/doc/tribool.boostbook
+++ b/doc/tribool.boostbook
@@ -138,6 +138,18 @@ if (indeterminate(x)) {
else {
// report success or failure of x
}
+
+ All the logical operators and methods of tribool
are marked
+ as constexpr
in C++11. It means that tribool
can
+ be used in compile time expressions:
+
+ constexpr tribool x = (tribool(true) || tribool(indeterminate));
+static_assert(x, "Must be true!");
+
+
+ Some compilers may have troubles with evaluating tribool::operator safe_bool()
at compile time.
+
+
diff --git a/include/boost/logic/tribool.hpp b/include/boost/logic/tribool.hpp
index 167a72a..c4788c1 100644
--- a/include/boost/logic/tribool.hpp
+++ b/include/boost/logic/tribool.hpp
@@ -14,7 +14,7 @@
#include
#include
-#if defined(_MSC_VER)
+#ifdef BOOST_HAS_PRAGMA_ONCE
# pragma once
#endif
@@ -59,9 +59,9 @@ typedef bool (*indeterminate_keyword_t)(tribool, detail::indeterminate_t);
* \returns x.value == tribool::indeterminate_value
* \throws nothrow
*/
-inline bool
+BOOST_CONSTEXPR inline bool
indeterminate(tribool x,
- detail::indeterminate_t dummy = detail::indeterminate_t());
+ detail::indeterminate_t dummy = detail::indeterminate_t()) BOOST_NOEXCEPT;
/**
* \brief A 3-state boolean type.
@@ -85,7 +85,7 @@ public:
*
* \throws nothrow
*/
- tribool() : value(false_value) {}
+ BOOST_CONSTEXPR tribool() BOOST_NOEXCEPT : value(false_value) {}
/**
* Construct a new 3-state boolean value with the given boolean
@@ -93,14 +93,14 @@ public:
*
* \throws nothrow
*/
- tribool(bool initial_value) : value(initial_value? true_value : false_value) {}
+ BOOST_CONSTEXPR tribool(bool initial_value) BOOST_NOEXCEPT : value(initial_value? true_value : false_value) {}
/**
* Construct a new 3-state boolean value with an indeterminate value.
*
* \throws nothrow
*/
- tribool(indeterminate_keyword_t) : value(indeterminate_value) {}
+ BOOST_CONSTEXPR tribool(indeterminate_keyword_t) BOOST_NOEXCEPT : value(indeterminate_value) {}
/**
* Use a 3-state boolean in a boolean context. Will evaluate true in a
@@ -109,7 +109,7 @@ public:
* \returns true if the 3-state boolean is true, false otherwise
* \throws nothrow
*/
- operator safe_bool() const
+ BOOST_CONSTEXPR operator safe_bool() const BOOST_NOEXCEPT
{
return value == true_value? &dummy::nonnull : 0;
}
@@ -123,7 +123,7 @@ public:
// Check if the given tribool has an indeterminate value. Also doubles as a
// keyword for the 'indeterminate' value
-inline bool indeterminate(tribool x, detail::indeterminate_t)
+BOOST_CONSTEXPR inline bool indeterminate(tribool x, detail::indeterminate_t) BOOST_NOEXCEPT
{
return x.value == tribool::indeterminate_value;
}
@@ -156,7 +156,7 @@ inline bool indeterminate(tribool x, detail::indeterminate_t)
*
* \throws nothrow
*/
-inline tribool operator!(tribool x)
+BOOST_CONSTEXPR inline tribool operator!(tribool x) BOOST_NOEXCEPT
{
return x.value == tribool::false_value? tribool(true)
:x.value == tribool::true_value? tribool(false)
@@ -196,38 +196,36 @@ inline tribool operator!(tribool x)
*
* \throws nothrow
*/
-inline tribool operator&&(tribool x, tribool y)
+BOOST_CONSTEXPR inline tribool operator&&(tribool x, tribool y) BOOST_NOEXCEPT
{
- if (static_cast(!x) || static_cast(!y))
- return false;
- else if (static_cast(x) && static_cast(y))
- return true;
- else
- return indeterminate;
+ return (static_cast(!x) || static_cast(!y))
+ ? tribool(false)
+ : ((static_cast(x) && static_cast(y)) ? tribool(true) : indeterminate)
+ ;
}
/**
* \overload
*/
-inline tribool operator&&(tribool x, bool y)
+BOOST_CONSTEXPR inline tribool operator&&(tribool x, bool y) BOOST_NOEXCEPT
{ return y? x : tribool(false); }
/**
* \overload
*/
-inline tribool operator&&(bool x, tribool y)
+BOOST_CONSTEXPR inline tribool operator&&(bool x, tribool y) BOOST_NOEXCEPT
{ return x? y : tribool(false); }
/**
* \overload
*/
-inline tribool operator&&(indeterminate_keyword_t, tribool x)
+BOOST_CONSTEXPR inline tribool operator&&(indeterminate_keyword_t, tribool x) BOOST_NOEXCEPT
{ return !x? tribool(false) : tribool(indeterminate); }
/**
* \overload
*/
-inline tribool operator&&(tribool x, indeterminate_keyword_t)
+BOOST_CONSTEXPR inline tribool operator&&(tribool x, indeterminate_keyword_t) BOOST_NOEXCEPT
{ return !x? tribool(false) : tribool(indeterminate); }
/**
@@ -263,38 +261,36 @@ inline tribool operator&&(tribool x, indeterminate_keyword_t)
*
* \throws nothrow
*/
-inline tribool operator||(tribool x, tribool y)
+BOOST_CONSTEXPR inline tribool operator||(tribool x, tribool y) BOOST_NOEXCEPT
{
- if (static_cast(!x) && static_cast(!y))
- return false;
- else if (static_cast(x) || static_cast(y))
- return true;
- else
- return indeterminate;
+ return (static_cast(!x) && static_cast(!y))
+ ? tribool(false)
+ : ((static_cast(x) || static_cast(y)) ? tribool(true) : tribool(indeterminate))
+ ;
}
/**
* \overload
*/
-inline tribool operator||(tribool x, bool y)
+BOOST_CONSTEXPR inline tribool operator||(tribool x, bool y) BOOST_NOEXCEPT
{ return y? tribool(true) : x; }
/**
* \overload
*/
-inline tribool operator||(bool x, tribool y)
+BOOST_CONSTEXPR inline tribool operator||(bool x, tribool y) BOOST_NOEXCEPT
{ return x? tribool(true) : y; }
/**
* \overload
*/
-inline tribool operator||(indeterminate_keyword_t, tribool x)
+BOOST_CONSTEXPR inline tribool operator||(indeterminate_keyword_t, tribool x) BOOST_NOEXCEPT
{ return x? tribool(true) : tribool(indeterminate); }
/**
* \overload
*/
-inline tribool operator||(tribool x, indeterminate_keyword_t)
+BOOST_CONSTEXPR inline tribool operator||(tribool x, indeterminate_keyword_t) BOOST_NOEXCEPT
{ return x? tribool(true) : tribool(indeterminate); }
//@}
@@ -331,34 +327,34 @@ inline tribool operator||(tribool x, indeterminate_keyword_t)
*
* \throws nothrow
*/
-inline tribool operator==(tribool x, tribool y)
+BOOST_CONSTEXPR inline tribool operator==(tribool x, tribool y) BOOST_NOEXCEPT
{
- if (indeterminate(x) || indeterminate(y))
- return indeterminate;
- else
- return (x && y) || (!x && !y);
+ return (indeterminate(x) || indeterminate(y))
+ ? indeterminate
+ : ((x && y) || (!x && !y))
+ ;
}
/**
* \overload
*/
-inline tribool operator==(tribool x, bool y) { return x == tribool(y); }
+BOOST_CONSTEXPR inline tribool operator==(tribool x, bool y) BOOST_NOEXCEPT { return x == tribool(y); }
/**
* \overload
*/
-inline tribool operator==(bool x, tribool y) { return tribool(x) == y; }
+BOOST_CONSTEXPR inline tribool operator==(bool x, tribool y) BOOST_NOEXCEPT { return tribool(x) == y; }
/**
* \overload
*/
-inline tribool operator==(indeterminate_keyword_t, tribool x)
+BOOST_CONSTEXPR inline tribool operator==(indeterminate_keyword_t, tribool x) BOOST_NOEXCEPT
{ return tribool(indeterminate) == x; }
/**
* \overload
*/
-inline tribool operator==(tribool x, indeterminate_keyword_t)
+BOOST_CONSTEXPR inline tribool operator==(tribool x, indeterminate_keyword_t) BOOST_NOEXCEPT
{ return tribool(indeterminate) == x; }
/**
@@ -394,34 +390,34 @@ inline tribool operator==(tribool x, indeterminate_keyword_t)
*
* \throws nothrow
*/
-inline tribool operator!=(tribool x, tribool y)
+BOOST_CONSTEXPR inline tribool operator!=(tribool x, tribool y) BOOST_NOEXCEPT
{
- if (indeterminate(x) || indeterminate(y))
- return indeterminate;
- else
- return !((x && y) || (!x && !y));
+ return (indeterminate(x) || indeterminate(y))
+ ? indeterminate
+ : !((x && y) || (!x && !y))
+ ;
}
/**
* \overload
*/
-inline tribool operator!=(tribool x, bool y) { return x != tribool(y); }
+BOOST_CONSTEXPR inline tribool operator!=(tribool x, bool y) BOOST_NOEXCEPT { return x != tribool(y); }
/**
* \overload
*/
-inline tribool operator!=(bool x, tribool y) { return tribool(x) != y; }
+BOOST_CONSTEXPR inline tribool operator!=(bool x, tribool y) BOOST_NOEXCEPT { return tribool(x) != y; }
/**
* \overload
*/
-inline tribool operator!=(indeterminate_keyword_t, tribool x)
+BOOST_CONSTEXPR inline tribool operator!=(indeterminate_keyword_t, tribool x) BOOST_NOEXCEPT
{ return tribool(indeterminate) != x; }
/**
* \overload
*/
-inline tribool operator!=(tribool x, indeterminate_keyword_t)
+BOOST_CONSTEXPR inline tribool operator!=(tribool x, indeterminate_keyword_t) BOOST_NOEXCEPT
{ return x != tribool(indeterminate); }
} } // end namespace boost::logic
diff --git a/include/boost/logic/tribool_io.hpp b/include/boost/logic/tribool_io.hpp
index 3ea52f3..0d7af8c 100644
--- a/include/boost/logic/tribool_io.hpp
+++ b/include/boost/logic/tribool_io.hpp
@@ -279,9 +279,9 @@ operator>>(std::basic_istream& in, tribool& x)
bool falsename_ok = true, truename_ok = true, othername_ok = true;
// Modeled after the code from Library DR 17
- while (falsename_ok && pos < falsename.size()
- || truename_ok && pos < truename.size()
- || othername_ok && pos < othername.size()) {
+ while ((falsename_ok && pos < falsename.size())
+ || (truename_ok && pos < truename.size())
+ || (othername_ok && pos < othername.size())) {
typename Traits::int_type c = in.get();
if (c == Traits::eof())
return in;
diff --git a/meta/libraries.json b/meta/libraries.json
new file mode 100644
index 0000000..d7e4934
--- /dev/null
+++ b/meta/libraries.json
@@ -0,0 +1,15 @@
+{
+ "key": "logic/tribool",
+ "name": "Tribool",
+ "authors": [
+ "Doug Gregor"
+ ],
+ "description": "3-state boolean type library.",
+ "documentation": "/doc/html/tribool.html",
+ "category": [
+ "Miscellaneous"
+ ],
+ "maintainers": [
+ "Douglas Gregor "
+ ]
+}
diff --git a/test/tribool_test.cpp b/test/tribool_test.cpp
index f25d512..be8fd18 100644
--- a/test/tribool_test.cpp
+++ b/test/tribool_test.cpp
@@ -114,6 +114,26 @@ int test_main(int, char*[])
BOOST_CHECK(false);
}
+#ifndef BOOST_NO_CXX11_CONSTEXPR
+ constexpr bool res_ors = indeterminate(false || tribool(false) || false || indeterminate); // true
+ BOOST_CHECK(res_ors);
+ char array_ors[res_ors ? 2 : 3];
+ BOOST_CHECK(sizeof(array_ors) / sizeof(char) == 2);
+
+ constexpr bool res_ands = !indeterminate(!(true && tribool(true) && true && indeterminate)); // false
+ BOOST_CHECK(!res_ands);
+ char array_ands[res_ands ? 2 : 3];
+ BOOST_CHECK(sizeof(array_ands) / sizeof(char) == 3);
+
+ // We avoid checking the tribool::operator safe_bool(),
+ // because GCC-4.8 fails to evaluate it at compile-time.
+ // Clang compiles well.
+ //
+ // constexpr bool res_safe_bool = tribool(true); // false
+ // constexpr tribool xxx = (tribool(true) || tribool(indeterminate));
+ // static_assert(xxx, "Must be true!");
+#endif
+
std::cout << "no errors detected\n";
return 0;
}