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Thepresence of this new type makes it unnecessary to use an <CODE>int</CODE> withthe values <CODE>0</CODE> and <CODE>1</CODE> and improves type safety. The twopossible values of a <CODE>bool</CODE> are <CODE>true</CODE> and <CODE>false</CODE>--theseare reserved words. The compiler knows how to coerce a <CODE>bool</CODE> intoan <CODE>int</CODE> and vice-versa.</P><P>If your compiler does not have the <CODE>bool</CODE> type and <CODE>false</CODE> and<CODE>true</CODE> keywords, an alternative is to produce such a type using a<CODE>typedef</CODE> of an enumeration representing the two possible values:</P><P><TABLE><tr><td> </td><td class=smallexample><FONT SIZE=-1><pre>enum boolvals { false, true };typedef enum boolvals bool;</FONT></pre></td></tr></table></P><P>What makes this simple alternative attractive is that it prevents havingto adjust the prolific amount of code that might use <CODE>bool</CODE> objectsonce your compiler supports the built-in type.</P><P><A NAME="Exceptions"></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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