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The newcasting operators are <CODE>static_cast</CODE>, <CODE>reinterpret_cast</CODE>,<CODE>dynamic_cast</CODE> and <CODE>const_cast</CODE>. They are reserved words.</P><P>These refined casting operators are vastly preferred over conventional Ccasts for C++ programming. In fact, even Stroustrup recommends that theolder style of C casts be banished from programming projects where atall possible <CITE>The C++ Programming Language, 3rd edition</CITE>. Reasonsfor preferring the new named casting operators include:</P><P><UL><LI>They provide the programmer with a mechanism for more explicitlyspecifying the kind of type conversion. This assists the compiler inidentifying incorrect conversions.<LI>They are easier to locate in source code, due to their uniquesyntax: <CODE>X_cast<type>(expr)</CODE>.</UL><P>If your compiler does not support the new casting operators, you mayhave to continue to use C-style casts--and carefully! I have seen oneproject agree to use macros such as the one shown below to encouragethose involved in the project to adopt the new operators. While thesyntax does not match that of the genuine operators, these macros makeit easy to later locate and alter the casts where they appear in sourcecode.</P><P><TABLE width=100%><tr><td> </td><td class=example bgcolor=#6688aa><br><pre>#define static_cast(T,e) (T) e</pre></td></tr></table></P><P><A NAME="Variable Scoping in For Loops"></A></TR></TABLE><BR> <FONT SIZE="-1">This document was generatedby <I>Gary V. Vaughan</I> on <I>September, 12 2004</I>using <A HREF="http://www.mathematik.uni-kl.de/~obachman/Texi2html"><I>texi2html</I></A></BODY></HTML>⌨️ 快捷键说明
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