item about Borland C++ dislike for objects in ternary operator added

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@3871 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

diff --git a/docs/html/standard.htm b/docs/html/standard.htm
index 61d507667eaa44249164f730501347ea6ffb3bf5..8cb5aab68b1fce4e80d8301fd29f3b5ae9c61d2e 100644 (file)
--- a/docs/html/standard.htm
+++ b/docs/html/standard.htm
@@ -50,6 +50,7 @@ C++ portability guide</A> by David Williams.
     <LI><A HREF="#no_stl">Don't use STL</A></LI>
     <LI><A HREF="#no_fordecl">Don't declare variables inside <TT>for()</TT></A></LI>
     <LI><A HREF="#no_nestedclasses">Don't use nested classes</A></LI>
     <LI><A HREF="#no_stl">Don't use STL</A></LI>
     <LI><A HREF="#no_fordecl">Don't declare variables inside <TT>for()</TT></A></LI>
     <LI><A HREF="#no_nestedclasses">Don't use nested classes</A></LI>

+    <LI><A HREF="#no_ternarywithobjects">Use ternary operator ?: carefully</A></LI>

   </OL>
   <BR>
   <LI>General recommendations</LI>
   </OL>
   <BR>
   <LI>General recommendations</LI>


@@ -332,6 +333,25 @@ you can try the following:
 <P>A nice side effect is that you don't need to recompile all the files
 including the header if you change the PrivateLibClass declaration (it's
 an example of a more general interface/implementation separation idea).
 <P>A nice side effect is that you don't need to recompile all the files
 including the header if you change the PrivateLibClass declaration (it's
 an example of a more general interface/implementation separation idea).

+
+  <P><LI><A NAME="no_ternarywithobjects"></A><B>Use ternary operator ?: carefully</B></LI><P>
+  The ternary operator <TT>?:</TT> shouldn't be used with objects (i.e. if any
+of its operands are objects) because some compilers (notable Borland C++) fail
+to compile such code.
+<P><U>Workaround</U>: use <TT>if/else</TT> instead.
+<PRE>
+    wxString s1, s2;
+
+    // Borland C++ won't compile the line below
+    wxString s = s1.Len() < s2.Len() ? s1 : s2;
+
+    // but any C++ compiler will compile this
+    wxString s;
+    if ( s1.Len() < s2.Len() )
+        s = s1;
+    else
+        s = s2;
+</PRE>

 </OL>
 
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 </OL>
 
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