Deferrer Struct Template Reference
[Miscellaneous constructs used by Vaucanson]
This class defers the creation of its template parameter.
More...
Public Member Functions | |
| Deferrer () | |
| Constructor. | |
| Deferrer & | operator= (const deferred_type &) |
| Effectively builds the holded type. | |
| operator T () const | |
| Get back the holded type. | |
Protected Attributes | |
| data_t | data |
| A flat area of memory big enough to hold an instance of deferred_type. | |
Detailed Description
template<class T, bool rt_checks = deferrer_runtime_checks_default>
struct vcsn::misc::Deferrer< T, rt_checks >
This class defers the creation of its template parameter.
This class is designed to hold a instance of type T, without initializing it when the class is created. In fact, the construction of T is deferred to a later time, using operator=. This may be usefull when you want to equip a class with a constructor without arguments.
Using a Deferrer may be dangerous, e.g. when you make a call to the cast operator without having initialized the referred type with a call to operator=.
Because of that danger, you can optionally enable or disable some runtime checks by respectively set or clear a second Boolean template parameter.
When you compile without the NDEBUG macro, this parameter defaults to true (checks enabled). Else it defaults to false (checks disabled).
Definition at line 96 of file deferrer.hh.
Member Data Documentation
data_t data [protected] |
A flat area of memory big enough to hold an instance of deferred_type.
Using this kind of trick forces us to do a lot of ugly casts (after all, data_t is just an array of char), but as a result there are no dynamic allocations.
Definition at line 132 of file deferrer.hh.
Referenced by Deferrer::operator T(), and Deferrer::operator=().
