16.2.1 Built-in bool type

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C++ introduced a built-in boolean data type called bool . The presence of this new type makes it unnecessary to use an int with the values and 1 and improves type safety. The two possible values of a bool are true and false --these are reserved words. The compiler knows how to coerce a bool into an int and vice-versa.

If your compiler does not have the bool type and false and true keywords, an alternative is to produce such a type using a typedef of an enumeration representing the two possible values:

 
 enum boolvals { false, true }; typedef enum boolvals bool; 

What makes this simple alternative attractive is that it prevents having to adjust the prolific amount of code that might use bool objects once your compiler supports the built-in type.


This document was generated by Gary V. Vaughan on May, 24 2001 using texi2html


GNU Autoconf, Automake and Libtool
GNU Autoconf, Automake, and Libtool
ISBN: 1578701902
EAN: 2147483647
Year: 2002
Pages: 290

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