From 0572dd371393295a4fdea0d133559548acbb25a5 Mon Sep 17 00:00:00 2001 From: John Maddock Date: Sat, 1 Feb 2003 12:12:08 +0000 Subject: [PATCH] Updated tests to stress new is_convertible and is_base_and_derived improvements. Updated docs accordingly. [SVN r17147] --- index.htm | 1959 ++++++++++++++++------------- test/is_base_and_derived_test.cpp | 12 +- test/is_convertible_test.cpp | 4 +- test/test.hpp | 3 + 4 files changed, 1102 insertions(+), 876 deletions(-) diff --git a/index.htm b/index.htm index ca3c307..873dc8b 100644 --- a/index.htm +++ b/index.htm @@ -1,14 +1,22 @@ - - Type Traits - - - - - -

Header <boost/type_traits.hpp>

-

Contents

- 
Introduction
+
+
+
+
+
+Type Traits
+
+
+
+
+
Header
+<boost/type_traits.hpp>

+
+
Contents

+
+
Introduction
 Primary Type Categorisation
 Secondary Type Categorisation
 Type Properties
@@ -18,843 +26,1026 @@
 Function Traits
 Type traits headers
 Example Code

-      
Introduction

-      
The contents of <boost/type_traits.hpp> are declared in namespace boost.

-      
The file <boost/type_traits.hpp> 
-         defines three kinds of type trait:

-      
    
-         
  1. 
-         The properties of a specific type.
-         
  2. 
-         The relationship between two types.
-         
  3. 
-            A transformation from one type to another.
    4. 
-      

-      
If you are new to this library then the accompanying 
-            article provides the background information and motivation.

-      
All of the integral expressions in this library are 
-            integral constant expressions, these can sometimes cause 
-         compiler problems in use, so there is a related set of 
-            coding guidelines to help you write portable code using this library.

-      
Primary Type Categorisation

-      
The following type traits templates identify which type category the type 
-         belongs to. For any given type, exactly one of the following expressions will 
-         evaluate to true. Note that this means that is_integral<T>::value
-         and is_float<T>::value will only every be true for built-in 
-         types; if you want to check for a user-defined type that may behave "as if" it 
-         is an integral or floating point type, then use the std::numeric_limits 
-         template instead.

-      
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
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-         
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-         
-         
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-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-      
 
Expression

-            
Description

-            
Reference

-            
Compiler 
-                  requirements

-            		 
 ::boost::is_void<T>::valueEvaluates to true only if T is a 
-               cv-qualified void type.
3.9.1p9

-            		  
 ::boost::is_integral<T>::valueEvaluates to true only if T is an 
-               cv-qualified integral type.
3.9.1p7

-            		  
 ::boost::is_float<T>::valueEvaluates to true only if T is a 
-               cv-qualified floating point type.
3.9.1p8

-            		  
 ::boost::is_pointer<T>::valueEvaluates to true only if T is 
-               cv-qualified pointer type (includes function pointers, but excludes pointers to 
-               members).
3.9.2p2

-               
8.3.1

-            		  
 ::boost::is_reference<T>::valueEvaluates to true only if T is a 
-               reference type.
3.9.2

-               
8.3.2

-            		If the compiler does not support 
-               partial-specialization of class templates, then this template may report the 
-               wrong result for function types. 
 ::boost::is_member_pointer<T>::valueEvaluates to true only if T is a 
-               cv-qualified pointer to a data-member or member-function.
3.9.2

-               
8.3.3

-            		  
 ::boost::is_array<T>::valueEvaluates to true only if T is an 
-               array type.
3.9.2

-               
8.3.4

-            		If the compiler does not support 
-               partial-specialization of class templates, then this template can give the 
-               wrong result with function types. 
 ::boost::is_union<T>::valueEvaluates to true only if T is of 
-               union type. Currently requires some kind of compiler support, otherwise unions 
-               are identified as classes.
3.9.2

-               
9.5

-            		Without (some as yet unspecified) 
-               help from the compiler, we cannot distinguish between union and class types, as 
-               a result this expression will never evaluate to true. 
 ::boost::is_class<T>::valueEvaluates to true only if T is of 
-               class/struct type.
3.9.2

-               
9.2

-            		Without (some as yet unspecified) 
-               help from the compiler, we cannot distinguish between union and class types, as 
-               a result this expression will eroneously evaluate to true for union types. 
 ::boost::is_enum<T>::valueEvaluates to true only if T is of 
-               enum type.
3.9.2

-               
7.2

-            		Requires a correctly functioning 
-               is_convertible template (this means that is_enum is currently broken under 
-               Borland C++ Builder 5, and some for some versions of the Metrowerks compiler). 
 ::boost::is_function<T>::valueEvaluates to true only if T is a function type 
-               (note not a reference or pointer to function).
3.9.2p1

-               
8.3.5

-            		If the compiler does not support 
-               partial-specialization of class templates, then this template does not compile 
-               for reference types. 

-      
 

-      
Secondary Type Categorisation

-      
The following type categories are made up of the union of one or more primary 
-         type categorisations. A type may belong to more than one of these categories, 
-         in addition to one of the primary categories.

-      
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-      
 
Expression

-            
Description

-            
Reference

-            
Compiler 
-                  requirements

-            		 
 ::boost::is_arithmetic<T>::valueEvaluates to true only if T is a 
-               cv-qualified arithmetic type. That is either an integral or floating point 
-               type.
3.9.1p8

-            		  
 ::boost::is_fundamental<T>::valueEvaluates to true only if T is an 
-               cv-qualified fundamental type. That is either an integral, a floating point, or 
-               a void type.
3.9.1

-            		  
 ::boost::is_object<T>::valueEvaluates to true only if T is a 
-               cv-qualified object type. That is not a function, reference, or void type.
3.9p9

-            		  
 ::boost::is_scalar<T>::valueEvaluates to true only if T is 
-               cv-qualified scalar type. That is an arithmetic, a pointer or a pointer to 
-               member type.
3.9p10

-            		If the compiler does not support 
-               partial-specialization of class templates, then this template can not be used 
-               with function types. 
 ::boost::is_compound<T>::valueEvaluates to true only if T is a 
-               compound type. That is an array, function, pointer, reference, enumerator, 
-               union, class or member function type.
3.9.2

-            		If the compiler does not support 
-               partial-specialization of class templates, then this template can not be used 
-               with function types. 
 ::boost::is_member_function_pointer<T>::valueEvaluates to true only if T is a pointer to a member 
-               function (and not a pointer to a member object). This template splits 
-               is_member_pointer into two sub-categories.
3.9.2

-               
8.3.3

-            		  

-      
 

-      
Type Properties

-      
The following templates identify the properties that a type has.

-      
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
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-            
-         
-         
-            
-            
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-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+
 
Expression

-            
Description

-            
Reference

-            
Compiler 
-                  requirements

-            		 
 ::boost::alignment_of<T>::valueIdentifies the alignment 
-               requirements of T. Actually returns a value that is only guaranteed to be a 
-               multiple of the actual alignment requirements of T   
 ::boost::is_empty<T>::valueTrue if T is an empty struct or 
-               class. If the compiler implements the "zero sized empty base classes" 
-               optimisation, then is_empty will correctly guess whether T is empty. Relies 
-               upon is_class to determine whether T is a class type.
-            
10p5

-            
Relies on the compiler 
-                  implementing zero sized empty base classes in order to detect empty classes.
-               

-               
Can not be used with incomplete types.

-               
Can not be used with union types, until is_union can be made to 
-                  work.

-               
If the compiler does not support partial-specialization of class 
-                  templates, then this template can not be used with abstract types.

-            		 
 ::boost::is_const<T>::valueEvaluates to true only if T is 
-               top-level const-qualified.
3.9.3

-            		  
 ::boost::is_volatile<T>::valueEvaluates to true only if T is 
-               volatile-qualified.
3.9.3

-            		  
::boost::is_polymorphic<T>::valueEvaluates to true only if T is a 
-               polymorphic type.10.3Requires knowledge of the compilers 
-               ABI, does actually seem to work with the magority of compilers though.
 ::boost::is_POD<T>::valueEvaluates to true only if T is a 
-               cv-qualified POD type.
3.9p10

-               
9p4

-            		Without some (as yet unspecified) 
-               help from the compiler, is_POD will never report that a class or struct is a 
-               POD; this is always safe, if possibly sub-optimal.
If the compiler does not 
-                  support partial-specialization of class templates, then this template can not 
-                  be used with function types.

-            		 
 ::boost::has_trivial_constructor<T>::valueTrue if T has a trivial default 
-               constructor.12.1p5
Without some (as yet 
-                  unspecified) help from the compiler, has_trivial_constructor will 
-                  never report that a class or struct has a trivial constructor; this is always 
-                  safe, if possibly sub-optimal.

-               
If the compiler does not support partial-specialization of class templates, 
-                  then this template can not be used with function types.

-            		 
 ::boost::has_trivial_copy<T>::valueTrue if T has a trivial copy 
-               constructor.12.8p6
Without some (as yet 
-                  unspecified) help from the compiler, has_trivial_copy will never 
-                  report that a class or struct has a trivial copy constructor; this is always 
-                  safe, if possibly sub-optimal.

-               
If the compiler does not support partial-specialization of class templates, 
-                  then this template can not be used with function types.

-            		 
 ::boost::has_trivial_assign<T>::valueTrue if T has a trivial assignment 
-               operator.12.8p11
Without some (as yet 
-                  unspecified) help from the compiler, has_trivial_assign will never 
-                  report that a class or struct has a trivial assignment operator; this is always 
-                  safe, if possibly sub-optimal.

-               
If the compiler does not support partial-specialization of class templates, 
-                  then this template can not be used with function types.

-            		 
 ::boost::has_trivial_destructor<T>::valueTrue if T has a trivial destructor.12.4p3
Without some (as yet 
-                  unspecified) help from the compiler, has_trivial_destructor will 
-                  never report that a class or struct has a trivial destructor; this is always 
-                  safe, if possibly sub-optimal.

-               
If the compiler does not support partial-specialization of class templates, 
-                  then this template can not be used with function types.

-            		 
 ::boost::is_stateless<T>::valueTrue if T is stateless, meaning 
-               that T has no storage and its constructors and destructors are trivial. 
Without some (as yet 
-                  unspecified) help from the compiler, is_stateless will never 
-                  report that a class or struct is_stateless; this is always safe, if possibly 
-                  sub-optimal.

-               
Will report true only if all of the following also report true:

-               
::boost::has_trivial_constructor<T>::value,
+
+
Introduction

+
+
The contents of <boost/type_traits.hpp> are declared in
+namespace boost.

+
+
The file <boost/type_traits.hpp>
+defines three kinds of type trait:

+
+
    
+    
  1. The properties of a specific type. 
    2. 
+    
  2. The relationship between two types. 
    3. 
+    
  3. A transformation from one type to another.
    4. 
+

+
+
If you are new to this library then the accompanying article provides the background
+information and motivation.

+
+
All of the integral expressions in this library are integral constant
+expressions, these can sometimes cause compiler problems
+in use, so there is a related set of coding guidelines
+to help you write portable code using this library.

+
+
Primary Type Categorisation

+
+
The following type traits templates identify which type
+category the type belongs to. For any given type, exactly one of
+the following expressions will evaluate to true. Note that this
+means that is_integral<T>::value and is_float<T>::value
+will only every be true for built-in types; if you want to check
+for a user-defined type that may behave "as if" it is
+an integral or floating point type, then use the std::numeric_limits
+template instead.

+
+
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+
 
Expression

+        
Description

+        
Reference

+        
Compiler requirements

+        		 
 ::boost::is_void<T>::valueEvaluates
+        to true only if T is a cv-qualified void type.
3.9.1p9

+        		  
 ::boost::is_integral<T>::valueEvaluates
+        to true only if T is an cv-qualified integral type.
3.9.1p7

+        		  
 ::boost::is_float<T>::valueEvaluates
+        to true only if T is a cv-qualified floating point type.
3.9.1p8

+        		  
 ::boost::is_pointer<T>::valueEvaluates
+        to true only if T is cv-qualified pointer type (includes
+        function pointers, but excludes pointers to members).
3.9.2p2

+        
8.3.1

+        		  
 ::boost::is_reference<T>::valueEvaluates
+        to true only if T is a reference type.
3.9.2

+        
8.3.2

+        		If the
+        compiler does not support partial-specialization of class
+        templates, then this template may report the wrong result
+        for function types. 
 ::boost::is_member_pointer<T>::valueEvaluates
+        to true only if T is a cv-qualified pointer to a data-member
+        or member-function.
3.9.2

+        
8.3.3

+        		  
 ::boost::is_array<T>::valueEvaluates
+        to true only if T is an array type.
3.9.2

+        
8.3.4

+        		If the
+        compiler does not support partial-specialization of class
+        templates, then this template can give the wrong result
+        with function types. 
 ::boost::is_union<T>::valueEvaluates
+        to true only if T is of union type. Currently requires
+        some kind of compiler support, otherwise unions are
+        identified as classes.
3.9.2

+        
9.5

+        		Without (some
+        as yet unspecified) help from the compiler, we cannot
+        distinguish between union and class types, as a result
+        this expression will never evaluate to true. 
 ::boost::is_class<T>::valueEvaluates
+        to true only if T is of class/struct type.
3.9.2

+        
9.2

+        		Without (some
+        as yet unspecified) help from the compiler, we cannot
+        distinguish between union and class types, as a result
+        this expression will eroneously evaluate to true for
+        union types. 
 ::boost::is_enum<T>::valueEvaluates
+        to true only if T is of enum type.
3.9.2

+        
7.2

+        		Requires a
+        correctly functioning is_convertible template (this means
+        that is_enum is currently broken under Borland C++
+        Builder 5, and some for some versions of the Metrowerks
+        compiler). 
 ::boost::is_function<T>::valueEvaluates to true only
+        if T is a function type (note not a reference or pointer
+        to function).
3.9.2p1

+        
8.3.5

+        		If the compiler does
+        not support partial-specialization of class templates,
+        then this template does not compile for reference types. 

+
+
 

+
+
Secondary Type Categorisation

+
+
The following type categories are made up of the union of one
+or more primary type categorisations. A type may belong to more
+than one of these categories, in addition to one of the primary
+categories.

+
+
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+
 
Expression

+        
Description

+        
Reference

+        
Compiler requirements

+        		 
 ::boost::is_arithmetic<T>::valueEvaluates
+        to true only if T is a cv-qualified arithmetic type. That
+        is either an integral or floating point type.
3.9.1p8

+        		  
 ::boost::is_fundamental<T>::valueEvaluates
+        to true only if T is an cv-qualified fundamental type.
+        That is either an integral, a floating point, or a void
+        type.
3.9.1

+        		  
 ::boost::is_object<T>::valueEvaluates
+        to true only if T is a cv-qualified object type. That is
+        not a function, reference, or void type.
3.9p9

+        		  
 ::boost::is_scalar<T>::valueEvaluates
+        to true only if T is cv-qualified scalar type. That is an
+        arithmetic, a pointer or a pointer to member type.
3.9p10

+        		If the
+        compiler does not support partial-specialization of class
+        templates, then this template can not be used with
+        function types. 
 ::boost::is_compound<T>::valueEvaluates
+        to true only if T is a compound type. That is an array,
+        function, pointer, reference, enumerator, union, class or
+        member function type.
3.9.2

+        		If the
+        compiler does not support partial-specialization of class
+        templates, then this template can not be used with
+        function types. 
 ::boost::is_member_function_pointer<T>::valueEvaluates to true only if T is a
+        pointer to a member function (and not a pointer to a
+        member object). This template splits is_member_pointer
+        into two sub-categories.
3.9.2

+        
8.3.3

+        		  

+
+
 

+
+
Type Properties

+
+
The following templates identify the properties that a type
+has.

+
+
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-      
 
Expression

+        
Description

+        
Reference

+        
Compiler requirements

+        		 
 ::boost::alignment_of<T>::valueIdentifies
+        the alignment requirements of T. Actually returns a value
+        that is only guaranteed to be a multiple of the actual
+        alignment requirements of T   
 ::boost::is_empty<T>::valueTrue if T
+        is an empty struct or class. If the compiler implements
+        the "zero sized empty base classes"
+        optimisation, then is_empty will correctly guess whether
+        T is empty. Relies upon is_class to determine whether T
+        is a class type. 
10p5

+        
Relies on the compiler implementing zero
+        sized empty base classes in order to detect empty classes.
+        

+        
Can not be used with incomplete types.

+        
Can not be used with union types, until
+        is_union can be made to work.

+        
If the compiler does not support partial-specialization
+        of class templates, then this template can not be used
+        with abstract types.

+        		 
 ::boost::is_const<T>::valueEvaluates
+        to true only if T is top-level const-qualified.
3.9.3

+        		  
 ::boost::is_volatile<T>::valueEvaluates
+        to true only if T is volatile-qualified.
3.9.3

+        		  
 ::boost::is_polymorphic<T>::valueEvaluates
+        to true only if T is a polymorphic type.10.3Requires
+        knowledge of the compilers ABI, does actually seem to
+        work with the magority of compilers though. 
 ::boost::is_POD<T>::valueEvaluates
+        to true only if T is a cv-qualified POD type.
3.9p10

+        
9p4

+        		Without
+        some (as yet unspecified) help from the compiler, is_POD
+        will never report that a class or struct is a POD; this
+        is always safe, if possibly sub-optimal.
If the
+        compiler does not support partial-specialization of class
+        templates, then this template can not be used with
+        function types.

+        		 
 ::boost::has_trivial_constructor<T>::valueTrue if T
+        has a trivial default constructor.12.1p5
Without some (as yet unspecified) help from
+        the compiler, has_trivial_constructor will
+        never report that a class or struct has a trivial
+        constructor; this is always safe, if possibly sub-optimal.

+        
If the compiler does not support partial-specialization
+        of class templates, then this template can not be used
+        with function types.

+        		 
 ::boost::has_trivial_copy<T>::valueTrue if T
+        has a trivial copy constructor.12.8p6
Without some (as yet unspecified) help from
+        the compiler, has_trivial_copy will never
+        report that a class or struct has a trivial copy
+        constructor; this is always safe, if possibly sub-optimal.

+        
If the compiler does not support partial-specialization
+        of class templates, then this template can not be used
+        with function types.

+        		 
 ::boost::has_trivial_assign<T>::valueTrue if T
+        has a trivial assignment operator.12.8p11
Without some (as yet unspecified) help from
+        the compiler, has_trivial_assign will never
+        report that a class or struct has a trivial assignment
+        operator; this is always safe, if possibly sub-optimal.

+        
If the compiler does not support partial-specialization
+        of class templates, then this template can not be used
+        with function types.

+        		 
 ::boost::has_trivial_destructor<T>::valueTrue if T
+        has a trivial destructor.12.4p3
Without some (as yet unspecified) help from
+        the compiler, has_trivial_destructor will
+        never report that a class or struct has a trivial
+        destructor; this is always safe, if possibly sub-optimal.

+        
If the compiler does not support partial-specialization
+        of class templates, then this template can not be used
+        with function types.

+        		 
 ::boost::is_stateless<T>::valueTrue if T
+        is stateless, meaning that T has no storage and its
+        constructors and destructors are trivial. 
Without some (as yet unspecified) help from
+        the compiler, is_stateless will never report
+        that a class or struct is_stateless; this is always safe,
+        if possibly sub-optimal.

+        
Will report true only if all of the
+        following also report true:

+        
::boost::has_trivial_constructor<T>::value,
 ::boost::has_trivial_copy<T>::value,
 ::boost::has_trivial_destructor<T>::value,
 ::boost::is_class<T>::value,
 ::boost::is_empty<T>::value

-               

-               
If the compiler does not support partial-specialization of class templates, 
-                  then this template can not be used with function types.

-            		 
 ::boost::has_nothrow_constructor<T>::valueTrue if T has a non-throwing default 
-               constructor. 
Without some (as yet 
-                  unspecified) help from the compiler, has_nothrow_constructor will 
-                  never report that a class or struct has a non-throwing constructor; this is 
-                  always safe, if possibly sub-optimal.

-               
If the compiler does not support partial-specialization of class 
-                  templates, then this template can not be used with function types.

-            		 
 ::boost::has_nothrow_copy<T>::valueTrue if T has a non-throwing copy constructor. 
Without some (as yet 
-                  unspecified) help from the compiler, has_nothrow_destructor will 
-                  never report that a class or struct has a non-throwing destructor; this is 
-                  always safe, if possibly sub-optimal.

-               
If the compiler does not support partial-specialization of class 
-                  templates, then this template can not be used with function types.

-            		 
 ::boost::has_nothrow_assign<T>::valueTrue if T has a non-throwing assignment 
-               operator. 
Without some (as yet 
-                  unspecified) help from the compiler, has_nothrow_destructor will 
-                  never report that a class or struct has a non-throwing assignment operator; 
-                  this is always safe, if possibly sub-optimal.

-               
If the compiler does not support partial-specialization of class 
-                  templates, then this template can not be used with function types.

-            		 

-      
 

-      
Relationships Between Types

-      
The following templates determine the whether there is a relationship between 
-         two types:

-      
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-      
 
Expression

-            
Description

-            
Reference

-            
Compiler 
-                  requirements

-            		 
 
::boost::is_same<T,U>::value

-               

-            
Evaluates to true if T 
-                  and U are the same type.

-            		 If the compiler does not support 
-               partial-specialization of class templates, then this template can not be used 
-               with abstract, incomplete or function types. 
 ::boost::is_convertible<T,U>::valueEvaluates to true if type T is 
-               convertible to type U.
Types T and U must not be incomplete, abstract or 
-                  function types.

-            
4

-               
8.5

-            		Note that this template is 
-               currently broken with Borland C++ Builder 5 (and earlier), for 
-               constructor-based conversions, and for the Metrowerks 7 (and earlier) compiler 
-               in all cases. 
 ::boost::is_base_and_derived<T,U>::valueEvaluates to true if type T is a base class to type U.
Types 
-                  T and U must not be incomplete types.

-            		10
This template relies upon a 
-                  functioning is_convertible template.

-               
If the compiler does not support partial-specialization of class 
-                  templates, then this template can not be used with function types.

-            		 

-      
Note that both is_convertible, and is_base_and_derived
-         can produce compiler errors if the convertion is ambiguous:

-      
struct A {};
+        
If the compiler does not support partial-specialization
+        of class templates, then this template can not be used
+        with function types.

+        		 
 ::boost::has_nothrow_constructor<T>::valueTrue if T has a non-throwing
+        default constructor. 
Without
+        some (as yet unspecified) help from the compiler, has_nothrow_constructor
+        will never report that a class or struct has a non-throwing
+        constructor; this is always safe, if possibly sub-optimal.

+        
If the compiler does not support partial-specialization
+        of class templates, then this template can not be used
+        with function types.

+        		 
 ::boost::has_nothrow_copy<T>::valueTrue if T has a non-throwing
+        copy constructor. 
Without
+        some (as yet unspecified) help from the compiler, has_nothrow_destructor
+        will never report that a class or struct has a non-throwing
+        destructor; this is always safe, if possibly sub-optimal.

+        
If the compiler does not support partial-specialization
+        of class templates, then this template can not be used
+        with function types.

+        		 
 ::boost::has_nothrow_assign<T>::valueTrue if T has a non-throwing
+        assignment operator. 
Without
+        some (as yet unspecified) help from the compiler, has_nothrow_destructor
+        will never report that a class or struct has a non-throwing
+        assignment operator; this is always safe, if possibly sub-optimal.

+        
If the compiler does not support partial-specialization
+        of class templates, then this template can not be used
+        with function types.

+        		 

+
+
 

+
+
Relationships Between Types

+
+
The following templates determine the whether there is a
+relationship between two types:

+
+
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+
 
Expression

+        
Description

+        
Reference

+        
Compiler requirements

+        		 
 
::boost::is_same<T,U>::value

+        
Evaluates to true if T and U are the same
+        type.

+        		 If the
+        compiler does not support partial-specialization of class
+        templates, then this template can not be used with
+        abstract, incomplete or function types. 
 ::boost::is_convertible<T,U>::valueEvaluates
+        to true if an imaginary lvalue of type T is convertible
+        to type U.
Type T must not be an incomplete type.

+        
Type U must not be an incomplete, abstract or function
+        type.

+        
No types are considered to be convertible to an array
+        type.

+        
4

+        
8.5

+        		Note that
+        this template is currently broken with Borland C++
+        Builder 5 (and earlier), for constructor-based
+        conversions, and for the Metrowerks 7 (and earlier)
+        compiler in all cases. 
 ::boost::is_base_and_derived<T,U>::valueEvaluates to true if type T is a
+        base class to type U.
Will detect non-public base
+        classes, and ambiguous base classes.

+        
Note that a class is not considered to be it's own
+        base class, likewise, if either T or U are non-class
+        types, then the result will always be false.

+        
Types T and U must not be incomplete types.

+        		10
If
+        the compiler does not support partial-specialization of
+        class templates, then this template can not be used with
+        function types.

+        		 

+
+
Note that both is_convertible, and is_base_and_derived
+can produce compiler errors if the convertion is ambiguous:

+
+
struct A {};
 struct B : A {};
 struct C : A {};
 struct D : B, C {};
 bool const x = boost::is_base_and_derived<A,D>::value;  // error
 bool const y = boost::is_convertible<D*,A*>::value;     // error
 

-      
Transformations Between Types

-      
The following templates transform one type to another, based upon some 
-         well-defined rule. Each template has a single member called type that is 
-         the result of applying the transformation to the template argument T:

-      
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-      
 
Expression

-            
Description

-            
Reference

-            
Compiler 
-                  requirements

-            		 
 ::boost::remove_const<T>::typeCreates a type the same as T but 
-               with any top level const qualifier removed. For example "const int" would 
-               become "int", but "const int*" would remain unchanged.3.9.3
If the compiler does not support 
-                  partial-specialization of class templates, then this template will compile, but 
-                  will have no effect, except where noted below.

-            		 
 ::boost::remove_volatile<T>::typeCreates a type the same as T but 
-               with any top level volatile qualifier removed. For example "volatile int" would 
-               become "int".
3.9.3

-            
If the compiler does not support 
-                  partial-specialization of class templates, then this template will compile, but 
-                  will have no effect, except where noted below.

-            		 
 ::boost::remove_cv<T>::typeCreates a type the same as T but with any top level 
-               cv-qualifiers removed. For example "const volatile int" would become "int".3.9.3
-               
If the compiler does not support partial-specialization of class 
-                  templates, then this template will compile, but will have no effect, except 
-                  where noted below.

-            		 
 ::boost::remove_reference<T>::typeIf T is a reference type then 
-               removes the reference, otherwise leaves T unchanged. For example "int&" 
-               becomes "int" but "int*" remains unchanged.8.3.2
-               
If the compiler does not support partial-specialization of class 
-                  templates, then this template will compile, but will have no effect, except 
-                  where noted below.

-            		 
 ::boost::remove_bounds<T>::typeIf T is an array type then removes 
-               the top level array qualifier from T, otherwise leaves T unchanged. For example 
-               "int[2][3]" becomes "int[3]".8.3.4
-               
If the compiler does not support partial-specialization of class 
-                  templates, then this template will compile, but will have no effect, except 
-                  where noted below.

-            		 
 ::boost::remove_pointer<T>::typeIf T is a pointer type, then 
-               removes the top-level indirection from T, otherwise leaves T unchanged. For 
-               example "int*" becomes "int", but "int&" remains unchanged.8.3.1
If the compiler does not support 
-                  partial-specialization of class templates, then this template will compile, but 
-                  will have no effect, except where noted below.

-            		 
 ::boost::add_reference<T>::typeIf T is a reference type then 
-               leaves T unchanged, otherwise converts T to a reference type. For example 
-               "int&" remains unchanged, but "double" becomes "double&".8.3.2
 

-            		 
 ::boost::add_pointer<T>::typeIf "t" is an instance of T, then 
-               add_pointer<T>::type is the type returned by "&t". For example "int" 
-               and "int&" both become "int*".8.3.1
-               
If the compiler does not support partial-specialization of class 
-                  templates, then this template will not compile with reference types.

-            		 
 ::boost::add_const<T>::typeThe same as "T const" for all T.3.9.3  
 ::boost::add_volatile<T>::typeThe same as "T volatile" for all T.3.9.3  
 ::boost::add_cv<T>::typeThe same as "T const volatile" for all T.3.9.3  

-      
As the table above indicates, support for partial specialization of class 
-         templates is required to correctly implement the type transformation templates. 
-         On the other hand, practice shows that many of the templates from this category 
-         are very useful, and often essential for implementing some generic libraries. 
-         Lack of these templates is often one of the major limiting factors in porting 
-         those libraries to compilers that do not yet support this language feature. As 
-         some of these compilers are going to be around for a while, and at least one of 
-         them is very wide-spread, it was decided that the library should provide 
-         workarounds where possible. The basic idea behind the workaround is

-      
    
-         
  1. 
-         To manually define full specializations of all type transformation templates 
-         for all fundamental types, and all their 1st and 2nd rank cv-[un]qualified 
-         derivative pointer types, and to
-         
  2. 
-            Provide a user-level macro that will define such explicit specializations for 
-            any user-defined type T.
    3. 
-      

-      
The first part guarantees the successful compilation of something like this:

-      
BOOST_STATIC_ASSERT((is_same<char, remove_reference<char&>::type>::value));

-      
BOOST_STATIC_ASSERT((is_same<char const, remove_reference<char const&>::type>::value));

-      
BOOST_STATIC_ASSERT((is_same<char volatile, remove_reference<char volatile&>::type>::value));

-      
BOOST_STATIC_ASSERT((is_same<char const volatile, remove_reference<char const volatile&>::type>::value));

-      
BOOST_STATIC_ASSERT((is_same<char*, remove_reference<char*&>::type>::value));

-      
BOOST_STATIC_ASSERT((is_same<char const*, remove_reference<char const*&>::type>::value));

-      
...

-      
BOOST_STATIC_ASSERT((is_same<char const volatile* const volatile* const volatile, remove_reference<char const volatile* const volatile* const volatile&>::type>::value));

-      
and the second part provides library's users with a mechanism to make the above 
-         code work not only for 'char', 'int' or other built-in type, but for they own 
-         types too:

-      
struct my {};

-      
BOOST_BROKEN_COMPILER_TYPE_TRAITS_SPECIALIZATION(my)

-      
BOOST_STATIC_ASSERT((is_same<my, remove_reference<my&>::type>::value));

-      
BOOST_STATIC_ASSERT((is_same<my, remove_const<my const>::type>::value));

-      
// etc.

-      
Note that the macro BOOST_BROKEN_COMPILER_TYPE_TRAITS_SPECIALIZATION evaluates 
-         to nothing on those compilers that do support partial specialization.

-      
Synthesizing Types

-      
The following template synthesizes a type with the desired properties.
-      

-      
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-      
 
Expression

-            
Description

-            
Reference

-            
Compiler 
-                  requirements

-            		 
 ::boost::type_with_alignment<Align>::typeAttempts to find a built-in or POD 
-               type with an alignment that is a multiple of Align.
-               

-      
Function Traits

-      
The ::boost::function_traits class template extracts information 
-         from function types.
-      

-      
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-         
-            
-            
-            
-            
-            
-            
-         
-      
 
Expression

-            
Description

-            
Reference

-            
Compiler 
-                  requirements

-            		 
 ::boost::function_traits<F>::arityDetermine the arity of the function 
-               type F.
-             Without partial specialisation support, this 
-               template does not compile for reference types. 
 ::boost::function_traits<F>::result_typeThe type returned by function type 
-                  F.
-             Does not compile without support for partial 
-               specialization of class templates. 
 ::boost::function_traits<F>::argN_typeThe Nth 
-               argument type of function type F, where 1<=N<=arity 
-               of F. Does not compile without support for partial 
-               specialization of class templates. 

-      
Type Traits Headers

-      
The type traits library is normally included with:

-      
#include <boost/type_traits.hpp>

-      
However the library is actually split up into a number of smaller headers, 
-         sometimes it can be convenient to include one of these directly in order to get 
-         just those type traits classes you actually need.  The split headers 
-         always have the same name as the template you require, and are located in 
-         boost/type_traits/.  So if for example some code requires 
-         is_class<>, then just include:

-      
<boost/type_traits/is_class.hpp>

-      
Example code

-      
Type-traits comes with four example programs that illustrate some of the ways 
-         in which the type traits templates may be used:

-      
Copy_example.cpp

-      
Demonstrates a version of std::copy that uses memcpy where appropriate to 
-         optimise the copy operation;

-      
//
+
+
Transformations Between Types

+
+
The following templates transform one type to another, based
+upon some well-defined rule. Each template has a single member
+called type that is the result of applying the
+transformation to the template argument T:

+
+
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+
 
Expression

+        
Description

+        
Reference

+        
Compiler requirements

+        		 
 ::boost::remove_const<T>::typeCreates a
+        type the same as T but with any top level const qualifier
+        removed. For example "const int" would become
+        "int", but "const int*" would remain
+        unchanged.3.9.3
If the
+        compiler does not support partial-specialization of class
+        templates, then this template will compile, but will have
+        no effect, except where noted below.

+        		 
 ::boost::remove_volatile<T>::typeCreates a
+        type the same as T but with any top level volatile
+        qualifier removed. For example "volatile int"
+        would become "int".
3.9.3

+        
If the
+        compiler does not support partial-specialization of class
+        templates, then this template will compile, but will have
+        no effect, except where noted below.

+        		 
 ::boost::remove_cv<T>::typeCreates a type the same as T but
+        with any top level cv-qualifiers removed. For example
+        "const volatile int" would become "int".3.9.3
If the compiler
+        does not support partial-specialization of class
+        templates, then this template will compile, but will have
+        no effect, except where noted below.

+        		 
 ::boost::remove_reference<T>::typeIf T is a
+        reference type then removes the reference, otherwise
+        leaves T unchanged. For example "int&"
+        becomes "int" but "int*" remains
+        unchanged.8.3.2
If the
+        compiler does not support partial-specialization of class
+        templates, then this template will compile, but will have
+        no effect, except where noted below.

+        		 
 ::boost::remove_bounds<T>::typeIf T is an
+        array type then removes the top level array qualifier
+        from T, otherwise leaves T unchanged. For example "int[2][3]"
+        becomes "int[3]".8.3.4
If the
+        compiler does not support partial-specialization of class
+        templates, then this template will compile, but will have
+        no effect, except where noted below.

+        		 
 ::boost::remove_pointer<T>::typeIf T is a
+        pointer type, then removes the top-level indirection from
+        T, otherwise leaves T unchanged. For example "int*"
+        becomes "int", but "int&" remains
+        unchanged.8.3.1
If the
+        compiler does not support partial-specialization of class
+        templates, then this template will compile, but will have
+        no effect, except where noted below.

+        		 
 ::boost::add_reference<T>::typeIf T is a
+        reference type then leaves T unchanged, otherwise
+        converts T to a reference type. For example "int&"
+        remains unchanged, but "double" becomes "double&".8.3.2  
 ::boost::add_pointer<T>::typeIf "t"
+        is an instance of T, then add_pointer<T>::type is
+        the type returned by "&t". For example
+        "int" and "int&" both become
+        "int*".8.3.1
If the
+        compiler does not support partial-specialization of class
+        templates, then this template will not compile with
+        reference types.

+        		 
 ::boost::add_const<T>::typeThe same as "T
+        const" for all T.3.9.3  
 ::boost::add_volatile<T>::typeThe same as "T
+        volatile" for all T.3.9.3  
 ::boost::add_cv<T>::typeThe same as "T
+        const volatile" for all T.3.9.3  

+
+
As the table above indicates, support for partial
+specialization of class templates is required to correctly
+implement the type transformation templates. On the other hand,
+practice shows that many of the templates from this category are
+very useful, and often essential for implementing some generic
+libraries. Lack of these templates is often one of the major
+limiting factors in porting those libraries to compilers that do
+not yet support this language feature. As some of these compilers
+are going to be around for a while, and at least one of them is
+very wide-spread, it was decided that the library should provide
+workarounds where possible. The basic idea behind the workaround
+is

+
+
    
+    
  1. To manually define full specializations of all type
+        transformation templates for all fundamental types, and
+        all their 1st and 2nd rank cv-[un]qualified derivative
+        pointer types, and to 
    2. 
+    
  2. Provide a user-level macro that will define such explicit
+        specializations for any user-defined type T.
    3. 
+

+
+
The first part guarantees the successful compilation of
+something like this:

+
+
BOOST_STATIC_ASSERT((is_same<char, remove_reference<char&>::type>::value));

+
+
BOOST_STATIC_ASSERT((is_same<char const, remove_reference<char const&>::type>::value));

+
+
BOOST_STATIC_ASSERT((is_same<char volatile, remove_reference<char volatile&>::type>::value));

+
+
BOOST_STATIC_ASSERT((is_same<char const volatile, remove_reference<char const volatile&>::type>::value));

+
+
BOOST_STATIC_ASSERT((is_same<char*, remove_reference<char*&>::type>::value));

+
+
BOOST_STATIC_ASSERT((is_same<char const*, remove_reference<char const*&>::type>::value));

+
+
...

+
+
BOOST_STATIC_ASSERT((is_same<char const volatile* const volatile* const volatile, remove_reference<char const volatile* const volatile* const volatile&>::type>::value));

+
+
and the second part provides library's users with a mechanism
+to make the above code work not only for 'char', 'int' or other
+built-in type, but for they own types too:

+
+
struct my {};

+
+
BOOST_BROKEN_COMPILER_TYPE_TRAITS_SPECIALIZATION(my)

+
+
BOOST_STATIC_ASSERT((is_same<my, remove_reference<my&>::type>::value));

+
+
BOOST_STATIC_ASSERT((is_same<my, remove_const<my const>::type>::value));

+
+
// etc.

+
+
Note that the macro
+BOOST_BROKEN_COMPILER_TYPE_TRAITS_SPECIALIZATION evaluates to
+nothing on those compilers that do support partial specialization.

+
+
Synthesizing Types

+
+
The following template synthesizes a type with the desired
+properties. 

+
+
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+
 
Expression

+        
Description

+        
Reference

+        
Compiler requirements

+        		 
 ::boost::type_with_alignment<Align>::typeAttempts
+        to find a built-in or POD type with an alignment that is
+        a multiple of Align.    

+
+
Function Traits

+
+
The ::boost::function_traits class template
+extracts information from function types. 

+
+
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+    
+        
+        
+        
+        
+        
+        
+    
+
 
Expression

+        
Description

+        
Reference

+        
Compiler requirements

+        		 
 ::boost::function_traits<F>::arityDetermine
+        the arity of the function type F.  Without partial
+        specialisation support, this template does not compile
+        for reference types. 
 ::boost::function_traits<F>::result_typeThe type
+        returned by function type F.  Does not compile
+        without support for partial specialization of class
+        templates. 
 ::boost::function_traits<F>::argN_typeThe Nth
+        argument type of function type F, where 1<=N<=arity
+        of F. Does not compile
+        without support for partial specialization of class
+        templates. 

+
+
Type Traits
+Headers

+
+
The type traits library is normally included with:

+
+
#include <boost/type_traits.hpp>

+
+
However the library is actually split up into a number of
+smaller headers, sometimes it can be convenient to include one of
+these directly in order to get just those type traits classes you
+actually need.  The split headers always have the same name
+as the template you require, and are located in boost/type_traits/. 
+So if for example some code requires is_class<>, then just
+include:

+
+
<boost/type_traits/is_class.hpp>

+
+
Example code

+
+
Type-traits comes with four example programs that illustrate
+some of the ways in which the type traits templates may be used:

+
+
Copy_example.cpp

+
+
Demonstrates a version of std::copy that uses memcpy where
+appropriate to optimise the copy operation;

+
+
//
 // opt::copy
 // same semantics as std::copy
 // calls memcpy where appropiate.
@@ -909,15 +1100,18 @@ inline I2 copy(I1 first, I1 last, I2 out)
          ::boost::has_trivial_assign<v1_t>::value
       >::value>::do_copy(first, last, out);
 }

-      
fill_example.cpp

-      
Demonstrates a version of std::fill that uses memset where appropriate to 
-         optimise fill operations. Also uses call_traits to optimise parameter passing, 
-         to avoid aliasing issues:

-      
namespace opt{
+
+
fill_example.cpp

+
+
Demonstrates a version of std::fill that uses memset where
+appropriate to optimise fill operations. Also uses call_traits to
+optimise parameter passing, to avoid aliasing issues:

+
+
namespace opt{
 //
 // fill
 // same as std::fill, uses memset where appropriate, along with call_traits
-// to "optimise" parameter passing.
+// to "optimise" parameter passing.
 //
 namespace detail{
 
@@ -971,11 +1165,15 @@ inline void fill(I first, I last, const T& val)
 }
 
 };   // namespace opt

-      
iter_swap_example.cpp

-      
Demonstrates a version of std::iter_swap that works with proxying iterators, as 
-         well as regular ones; calls std::swap for regular iterators, otherwise does a 
-         "slow but safe" swap:

-      
namespace opt{
+
+
iter_swap_example.cpp

+
+
Demonstrates a version of std::iter_swap that works with
+proxying iterators, as well as regular ones; calls std::swap for
+regular iterators, otherwise does a "slow but safe"
+swap:

+
+
namespace opt{
 //
 // iter_swap:
 // tests whether iterator is a proxying iterator or not, and
@@ -1023,11 +1221,15 @@ inline void iter_swap(I1 one, I2 two)
 }
 
 };   // namespace opt

-      
Trivial_destructor_example.cpp

-      
This algorithm is the reverse of std::unitialized_copy; it takes a block of 
-         initialized memory and calls destructors on all objects therein. This would 
-         typically be used inside container classes that manage their own memory:

-      
namespace opt{
+
+
Trivial_destructor_example.cpp

+
+
This algorithm is the reverse of std::unitialized_copy; it
+takes a block of initialized memory and calls destructors on all
+objects therein. This would typically be used inside container
+classes that manage their own memory:

+
+
namespace opt{
 //
 // algorithm destroy_array:
 // The reverse of std::unitialized_copy, takes a block of
@@ -1068,24 +1270,35 @@ inline void destroy_array(T* p1, T* p2)
    detail::array_destroyer<boost::has_trivial_destructor<T>::value>::destroy_array(p1, p2);
 }
 } // namespace opt

-      

-      
Revised 22 April 2001

-      
Documentation © Copyright John Maddock 2001. Permission to copy, use, modify, 
-         sell and distribute this document is granted provided this copyright notice 
-         appears in all copies. This document is provided "as is" without express or 
-         implied warranty, and with no claim as to its suitability for any purpose.

-      
The type traits library is based on contributions by Steve Cleary, Beman Dawes, 
-         Aleksey Gurtovoy, Howard Hinnant, Jesse Jones, Mat Marcus, John Maddock and 
-         Jeremy Siek.

-      
Mat Marcus and Jesse Jones have worked on, and published a 
-            paper describing the partial specialisation workarounds used in this 
-         library.

-      
The is_convertible template is based on code originally devised by Andrei 
-         Alexandrescu, see "Generic<Programming>: 
-            Mappings between Types and Values".

-      
Maintained by John Maddock, the 
-         latest version of this file can be found at www.boost.org, 
-         and the boost discussion list at boost@lists.boost.org
-         (see http://www.boost.org/more/mailing_lists.htm#main).

-   
+
+

+
+
Revised 22 April 2001

+
+
Documentation © Copyright John Maddock 2001. Permission to
+copy, use, modify, sell and distribute this document is granted
+provided this copyright notice appears in all copies. This
+document is provided "as is" without express or implied
+warranty, and with no claim as to its suitability for any purpose.

+
+
The type traits library is based on contributions by Steve
+Cleary, Beman Dawes, Aleksey Gurtovoy, Howard Hinnant, Jesse
+Jones, Mat Marcus, John Maddock and Jeremy Siek.

+
+
Mat Marcus and Jesse Jones have worked on, and published a paper
+describing the partial specialisation workarounds used in this
+library.

+
+
The is_convertible template is based on code originally
+devised by Andrei Alexandrescu, see "Generic<Programming>:
+Mappings between Types and Values".

+
+
Maintained by John
+Maddock, the latest version of this file can be found at www.boost.org, and the boost
+discussion list at boost@lists.boost.org
+(see http://www.boost.org/more/mailing_lists.htm#main).

+
 
diff --git a/test/is_base_and_derived_test.cpp b/test/is_base_and_derived_test.cpp
index 94d6cec..24d155d 100644
--- a/test/is_base_and_derived_test.cpp
+++ b/test/is_base_and_derived_test.cpp
@@ -4,16 +4,23 @@
 //  in all copies. This software is provided "as is" without express or implied
 //  warranty, and with no claim as to its suitability for any purpose.
 
+
 #include "test.hpp"
 #include "check_integral_constant.hpp"
 #include TYPE_TRAITS(is_base_and_derived)
 
+
+
 TT_TEST_BEGIN(is_base_and_derived)
 
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), false);
-BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), true);
-BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), true);
+BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), false);
+BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), false);
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), true);
+BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), true);
+BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), true);
+BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), true);
+BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), true);
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), false);
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), false);
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_base_and_derived::value), false);
@@ -34,3 +41,4 @@ TT_TEST_END
 
 
 
+
diff --git a/test/is_convertible_test.cpp b/test/is_convertible_test.cpp
index 1f37842..4bcc2db 100644
--- a/test/is_convertible_test.cpp
+++ b/test/is_convertible_test.cpp
@@ -49,6 +49,8 @@ BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible::value), t
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible::value), true);
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible::value), true);
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible::value), false);
+BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible::value), false);
+BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible::value), true);
 
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible::value), true);
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible::value), false);
@@ -60,7 +62,7 @@ BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible::value), true);
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible >::value), true);
diff --git a/test/test.hpp b/test/test.hpp
index 9c678fb..ddae8f2 100644
--- a/test/test.hpp
+++ b/test/test.hpp
@@ -180,6 +180,9 @@ union empty_POD_union_UDT{};
 class Base { };
 
 class Derived : public Base { };
+class Derived2 : public Base { };
+class MultiBase : public Derived, public Derived2 {};
+class PrivateBase : private Base {};
 
 class NonDerived { };