From ff0cb364168707e47378fe87d68586131f957e8f Mon Sep 17 00:00:00 2001 From: Daniel Walker Date: Sat, 1 Sep 2012 20:00:33 +0000 Subject: [PATCH] Fixes [6754]. Minor edits to documentation. [SVN r80352] --- test/result_of_test.cpp | 106 ++++++++++++++++++++++------------------ utility.htm | 34 ++++++------- 2 files changed, 76 insertions(+), 64 deletions(-) diff --git a/test/result_of_test.cpp b/test/result_of_test.cpp index c006d35..3f6da9e 100644 --- a/test/result_of_test.cpp +++ b/test/result_of_test.cpp @@ -7,10 +7,6 @@ #include -#ifndef BOOST_NO_DECLTYPE -# define BOOST_RESULT_OF_USE_DECLTYPE -#endif - // For more information, see http://www.boost.org/libs/utility #include #include @@ -66,6 +62,9 @@ struct int_result_type_and_float_result_of_and_char_return_template char operator()(char); }; +template +struct cv_overload_check {}; + struct result_of_member_function_template { template struct result; @@ -73,13 +72,13 @@ struct result_of_member_function_template template struct result { typedef That type; }; template typename result::type operator()(T); - template struct result { typedef const That type; }; + template struct result { typedef cv_overload_check type; }; template typename result::type operator()(T) const; - template struct result { typedef volatile That type; }; + template struct result { typedef cv_overload_check type; }; template typename result::type operator()(T) volatile; - template struct result { typedef const volatile That type; }; + template struct result { typedef cv_overload_check type; }; template typename result::type operator()(T) const volatile; template struct result { typedef That & type; }; @@ -95,13 +94,16 @@ struct result_of_member_function_template template typename result::type operator()(T const volatile &, T); }; -struct no_result_type_or_result_of +struct no_result_type_or_result { - int operator()(double); - short operator()(double) const; - unsigned int operator()(); - unsigned short operator()() volatile; - const unsigned short operator()() const volatile; + short operator()(double); + cv_overload_check operator()(double) const; + cv_overload_check operator()(double) volatile; + cv_overload_check operator()(double) const volatile; + int operator()(); + cv_overload_check operator()() const; + cv_overload_check operator()() volatile; + cv_overload_check operator()() const volatile; #if !defined(BOOST_NO_RVALUE_REFERENCES) short operator()(int&&); int operator()(int&); @@ -110,13 +112,16 @@ struct no_result_type_or_result_of }; template -struct no_result_type_or_result_of_template +struct no_result_type_or_result_template { - int operator()(double); - short operator()(double) const; - unsigned int operator()(); - unsigned short operator()() volatile; - const unsigned short operator()() const volatile; + short operator()(double); + cv_overload_check operator()(double) const; + cv_overload_check operator()(double) volatile; + cv_overload_check operator()(double) const volatile; + int operator()(); + cv_overload_check operator()() const; + cv_overload_check operator()() volatile; + cv_overload_check operator()() const volatile; #if !defined(BOOST_NO_RVALUE_REFERENCES) short operator()(int&&); int operator()(int&); @@ -161,7 +166,7 @@ int main() // Prior to decltype, result_of could not deduce the return type // nullary function objects unless they exposed a result_type. -#if !defined(BOOST_NO_DECLTYPE) +#if defined(BOOST_RESULT_OF_USE_DECLTYPE) BOOST_STATIC_ASSERT((is_same::type, int>::value)); BOOST_STATIC_ASSERT((is_same::type, int>::value)); BOOST_STATIC_ASSERT((is_same(void)>::type, int>::value)); @@ -173,14 +178,11 @@ int main() BOOST_STATIC_ASSERT((is_same(void)>::type, void>::value)); #endif - BOOST_STATIC_ASSERT((is_same::type, int>::value)); - BOOST_STATIC_ASSERT((is_same(char)>::type, int>::value)); - // Prior to decltype, result_of ignored a nested result<> if // result_type was defined. After decltype, result_of deduces the // actual return type of the function object, ignoring both // result<> and result_type. -#if !defined(BOOST_NO_DECLTYPE) +#if defined(BOOST_RESULT_OF_USE_DECLTYPE) BOOST_STATIC_ASSERT((is_same::type, char>::value)); BOOST_STATIC_ASSERT((is_same(char)>::type, char>::value)); #else @@ -188,6 +190,9 @@ int main() BOOST_STATIC_ASSERT((is_same(char)>::type, int>::value)); #endif + BOOST_STATIC_ASSERT((is_same::type, int>::value)); + BOOST_STATIC_ASSERT((is_same(char)>::type, int>::value)); + BOOST_STATIC_ASSERT((is_same::type, int>::value)); BOOST_STATIC_ASSERT((is_same::type, int>::value)); BOOST_STATIC_ASSERT((is_same::type, int>::value)); @@ -211,18 +216,18 @@ int main() BOOST_STATIC_ASSERT((is_same::type, int>::value)); BOOST_STATIC_ASSERT((is_same::type, double>::value)); - BOOST_STATIC_ASSERT((is_same::type, const double>::value)); - BOOST_STATIC_ASSERT((is_same::type, volatile double>::value)); - BOOST_STATIC_ASSERT((is_same::type, const volatile double>::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); BOOST_STATIC_ASSERT((is_same::type, int &>::value)); BOOST_STATIC_ASSERT((is_same::type, int const &>::value)); BOOST_STATIC_ASSERT((is_same::type, int volatile &>::value)); BOOST_STATIC_ASSERT((is_same::type, int const volatile &>::value)); BOOST_STATIC_ASSERT((is_same::type, double>::value)); - BOOST_STATIC_ASSERT((is_same::type, const double>::value)); - BOOST_STATIC_ASSERT((is_same::type, volatile double>::value)); - BOOST_STATIC_ASSERT((is_same::type, const volatile double>::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); BOOST_STATIC_ASSERT((is_same::type, int &>::value)); BOOST_STATIC_ASSERT((is_same::type, int const &>::value)); BOOST_STATIC_ASSERT((is_same::type, int volatile &>::value)); @@ -235,24 +240,31 @@ int main() BOOST_STATIC_ASSERT((is_same::type, int>::value)); BOOST_STATIC_ASSERT((is_same::type,int>::value)); -#if !defined(BOOST_NO_DECLTYPE) - BOOST_STATIC_ASSERT((is_same::type, int>::value)); - BOOST_STATIC_ASSERT((is_same::type, unsigned int>::value)); - BOOST_STATIC_ASSERT((is_same::type, short>::value)); - BOOST_STATIC_ASSERT((is_same::type, unsigned short>::value)); - BOOST_STATIC_ASSERT((is_same::type, const unsigned short>::value)); - BOOST_STATIC_ASSERT((is_same(double)>::type, int>::value)); - BOOST_STATIC_ASSERT((is_same(void)>::type, unsigned int>::value)); - BOOST_STATIC_ASSERT((is_same(double)>::type, short>::value)); - BOOST_STATIC_ASSERT((is_same(void)>::type, unsigned short>::value)); - BOOST_STATIC_ASSERT((is_same(void)>::type, const unsigned short>::value)); +#if defined(BOOST_RESULT_OF_USE_DECLTYPE) + BOOST_STATIC_ASSERT((is_same::type, short>::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same::type, int>::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same::type, cv_overload_check >::value)); + + BOOST_STATIC_ASSERT((is_same(double)>::type, short>::value)); + BOOST_STATIC_ASSERT((is_same(double)>::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same(double)>::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same(double)>::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same(void)>::type, int>::value)); + BOOST_STATIC_ASSERT((is_same(void)>::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same(void)>::type, cv_overload_check >::value)); + BOOST_STATIC_ASSERT((is_same(void)>::type, cv_overload_check >::value)); #if !defined(BOOST_NO_RVALUE_REFERENCES) - BOOST_STATIC_ASSERT((is_same::type, short>::value)); - BOOST_STATIC_ASSERT((is_same::type, int>::value)); - BOOST_STATIC_ASSERT((is_same::type, long>::value)); - BOOST_STATIC_ASSERT((is_same(int&&)>::type, short>::value)); - BOOST_STATIC_ASSERT((is_same(int&)>::type, int>::value)); - BOOST_STATIC_ASSERT((is_same(int const&)>::type, long>::value)); + BOOST_STATIC_ASSERT((is_same::type, short>::value)); + BOOST_STATIC_ASSERT((is_same::type, int>::value)); + BOOST_STATIC_ASSERT((is_same::type, long>::value)); + BOOST_STATIC_ASSERT((is_same(int&&)>::type, short>::value)); + BOOST_STATIC_ASSERT((is_same(int&)>::type, int>::value)); + BOOST_STATIC_ASSERT((is_same(int const&)>::type, long>::value)); #endif #endif diff --git a/utility.htm b/utility.htm index 65ead22..73bd692 100644 --- a/utility.htm +++ b/utility.htm @@ -163,7 +163,7 @@ void f() {

If your compiler's support for decltype is adequate, result_of automatically uses it to - deduce the result type of your callable.

+ deduce the result type of your callable object.

#include <boost/utility/result_of.hpp>
@@ -182,7 +182,7 @@ typedef boost::result_of<

You can test whether result_of is using - decltype checking if the macro + decltype by checking if the macro BOOST_RESULT_OF_USE_DECLTYPE is defined after including result_of.hpp. You can also force result_of to use decltype by @@ -230,27 +230,27 @@ typedef boost::result_of< >::type type; // type is int -

If you are writing a reusable function object - that should work with result_of, for +

Since decltype is a new language + feature recently standardized in C++11, + if you are writing a function object + to be used with result_of, for maximum portability, you might consider following the above protocol even if your compiler has - proper decltype support. If you do, - take care to ensure that the + proper decltype support. If you wish to continue to + use the protocol on compilers that + support decltype, there are two options: + You can use boost::tr1_result_of, which is also + defined in <boost/utility/result_of.hpp>. + Alternatively, you can define the macro + BOOST_RESULT_OF_USE_TR1, which causes + result_of to use the protocol described + above instead of decltype. If you choose to + follow the protocol, take care to ensure that the result_type and result<> members accurately represent the return type of operator().

-

If you wish to continue to - use the protocol on compilers that - support decltype, - use boost::tr1_result_of, which is also - defined - in <boost/utility/result_of.hpp>. You can also define the macro - BOOST_RESULT_OF_USE_TR1, which causes - result_of to use the convention described - above instead of decltype.

-

This implementation of result_of requires class template partial specialization, the @@ -266,7 +266,7 @@ typedef boost::result_of< N1836, or, for motivation and design rationale, the result_of proposal.

- Contributed by Doug Gregor.

+

Created by Doug Gregor. Contributions from Daniel Walker, Eric Niebler, Michel Morin and others

Class templates for the Base-from-Member Idiom

See separate documentation.