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
This commit is contained in:
Vadim Zeitlin
1999-10-07 16:02:11 +00:00
parent 2b37dc19c5
commit 00ded55423

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@@ -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_ternarywithobjects">Use ternary operator ?: carefully</A></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><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>
<BR>