Fixed some formatting.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32392 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bill Wendling 2006-12-09 01:35:43 +00:00
parent 0f7c10d7b6
commit 4ad6d61cb7

View File

@ -49,7 +49,7 @@
<li><a href="#ll_assert">Assert Liberally</a></li>
<li><a href="#ll_ns_std">Do not use 'using namespace std'</a></li>
<li><a href="#ll_virtual_anch">Provide a virtual method anchor for
clases in headers</a></li>
classes in headers</a></li>
<li><a href="#ll_preincrement">Prefer Preincrement</a></li>
<li><a href="#ll_avoidendl">Avoid <tt>std::endl</tt></a></li>
</ol></li>
@ -616,42 +616,43 @@ assert(isa&lt;PHINode&gt;(Succ-&gt;front()) &amp;&amp; "Only works on PHId BBs!"
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
<a name="ll_ns_std">Do not use 'using namespace std'</a>
<a name="ll_ns_std">Do not use '<tt>using namespace std</tt>'</a>
</div>
<div class="doc_text">
<p>In LLVM, we prefer to explicitly prefix all identifiers from the standard
namespace with an "std::" prefix, rather than rely on "using namespace std;".
</p>
namespace with an "<tt>std::</tt>" prefix, rather than rely on
"<tt>using namespace std;</tt>".</p>
<p> In header files, adding a 'using namespace XXX' directive pollutes the
namespace of any source file that includes the header. This is clearly a bad
thing.</p>
<p> In header files, adding a '<tt>using namespace XXX</tt>' directive pollutes
the namespace of any source file that includes the header. This is clearly a
bad thing.</p>
<p>In implementation files (e.g. .cpp files) the rule is more of a stylistic
rule, but is still important. Basically, using explicit namespace prefixes
makes
the code <b>more clear</b> - because it is immediately obvious what facilities
are being used and where they are coming from - and <b>more portable</b> -
because namespace clashes cannot occur between LLVM code and other namespaces.
The portability rule is important because different standard library
implementations expose different symbols (potentially ones they shouldn't) and
future revisions to the C++ standard will add more symbols to the std
namespace. As such, we never 'using namespace std;' in LLVM.</p>
<p>In implementation files (e.g. .cpp files), the rule is more of a stylistic
rule, but is still important. Basically, using explicit namespace prefixes
makes the code <b>clearer</b>, because it is immediately obvious what facilities
are being used and where they are coming from, and <b>more portable</b>, because
namespace clashes cannot occur between LLVM code and other namespaces. The
portability rule is important because different standard library implementations
expose different symbols (potentially ones they shouldn't), and future revisions
to the C++ standard will add more symbols to the <tt>std</tt> namespace. As
such, we never use '<tt>using namespace std;</tt>' in LLVM.</p>
<p>The exception to the general rule (i.e. it's not an exception for the std
namespace) is for implementation files. For example, all of the code in the
LLVM project implements code that lives in the 'llvm' namespace. As such, it
is ok, and actually more clear, for the .cpp files to have a 'using namespace
llvm' directive at their top, after the #includes. The general form of this
rule is that any .cpp file that implements code in any namespace may use that
namespace (and its parents), but should not use any others.</p>
<p>The exception to the general rule (i.e. it's not an exception for
the <tt>std</tt> namespace) is for implementation files. For example, all of
the code in the LLVM project implements code that lives in the 'llvm' namespace.
As such, it is ok, and actually clearer, for the .cpp files to have a '<tt>using
namespace llvm</tt>' directive at their top, after the <tt>#include</tt>s. The
general form of this rule is that any .cpp file that implements code in any
namespace may use that namespace (and its parents'), but should not use any
others.</p>
</div>
<!-- _______________________________________________________________________ -->
<div class="doc_subsubsection">
<a name="ll_virtual_anch">Provide a virtual method anchor for clases in headers</a>
<a name="ll_virtual_anch">Provide a virtual method anchor for classes
in headers</a>
</div>
<div class="doc_text">