feedc0de/boost_concept_check
1
0
Fork 0
forked from boostorg/concept_check
Code Pull Requests Activity

*** empty log message ***

Browse Source 
[SVN r15038]
This commit is contained in:
Jeremy Siek
2002-08-21 16:30:48 +00:00
parent 5fface1ce0
commit 2ebed5a25a
8 changed files with 79 additions and 29 deletions
Download Patch File Download Diff File Expand all files Collapse all files
implementation.htm
+7 -8
View File
@@ -129,7 +129,7 @@ everything in a do-while loop to prevent name collisions.
</pre>
To check the type parameters of class templates, we provide the
<tt>BOOST_CLASS_REQUIRES</tt> macro which can be used inside the body of a
<tt>BOOST_CLASS_REQUIRE</tt> macro which can be used inside the body of a
class definition (whereas <tt>function_requires()</tt> can only be used
inside of a function body). This macro declares a nested class
template, where the template parameter is a function pointer. We then
@@ -139,23 +139,22 @@ of the constraint function as the template argument. We use the
typedef names to help prevent name collisions.
<pre>
#define BOOST_CLASS_REQUIRES(type_var, concept) \
typedef void (concept &lt;type_var&gt;::* func##type_var##concept)(); \
#define BOOST_CLASS_REQUIRE(type_var, ns, concept) \
typedef void (ns::concept &lt;type_var&gt;::* func##type_var##concept)(); \
template &lt;func##type_var##concept _Tp1&gt; \
struct concept_checking_##type_var##concept { }; \
typedef concept_checking_##type_var##concept&lt; \
BOOST_FPTR concept &lt;type_var&gt;::constraints&gt; \
BOOST_FPTR ns::concept&lt;type_var&gt;::constraints&gt; \
concept_checking_typedef_##type_var##concept
</pre>
In addition, there are versions of <tt>BOOST_CLASS_REQUIRES</tt> that
In addition, there are versions of <tt>BOOST_CLASS_REQUIRE</tt> that
take more arguments, to handle concepts that include interactions
between two or more types. <tt>BOOST_CLASS_REQUIRES</tt> was not used
in the implementation of the BCCL concept checks because several
between two or more types. <tt>BOOST_CLASS_REQUIRE</tt> was not used
in the implementation of the BCCL concept checks because some
compilers do not implement template parameters of function pointer
type.
<!-- We decided not to go with this version since it is easier to misuse
To check the type parameters of class templates, we provide the