SafeBool_T.h File Reference

#include <dds/Versioned_Namespace.h>

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Classes
class	OpenDDS::DCPS::SafeBoolBase
class	OpenDDS::DCPS::SafeBool_T< DerivedNonVirtual >
class	OpenDDS::DCPS::SafeBool_T< void >

Namespaces
	OpenDDS
	The Internal API and Implementation of OpenDDS.
	OpenDDS::DCPS

Functions
template<typename X , typename Y >
bool	OpenDDS::DCPS::operator== (const SafeBool_T< X > &x, const SafeBool_T< Y > &)
template<typename X , typename Y >
bool	OpenDDS::DCPS::operator!= (const SafeBool_T< X > &x, const SafeBool_T< Y > &)

Detailed Description

Implements the "Safe Bool" idiom, which is a safer alternative to operator bool. Based on: https://www.artima.com/articles/the-safe-bool-idiom TLDR: We may want to be able to use operator bool() to check an object's abstract truthfulness using if (object) {...}, but that opens up implicit casting and comparisons that come with the bool type that are almost certainly not desired, like int count = object. This is achieved via the BoolType function pointer which isn't actually called, but is the only boolean-ish thing the type can be implicitly converted to using the BoolType operator.

If you want the boolean test function to be virtual, implement it as: virtual bool boolean_test() const; and derive the class from SafeBool_T with no template argument: class YourClass : public SafeBool_T<>.

If you do NOT want the boolean test function to be virtual, implement it as: bool boolean_test() const; and derive the class from SafeBool_T with the class as the template argument: class YourClass : public SafeBool_T<YourClass>.

Definition in file SafeBool_T.h.