Implementing singleton into multiply classes

[John Eskie]

Lets say I want to make multiply classes as singletons. A singleton skeleton
would be with a static member variable of the instance and a GetInstance
function.
Currently I have this functionality in all the classes where I need it but
I'd like to use templates or some other language construct so I can remove
the duplicated code.
A small example of what I'd like to do:

Singleton class functionality:
T *instance;
T *GetInstance();
....
class A
{
....implements the above
int varA;
};

Class B
{
.... also implements singleton
double varB;
};

Thanks in advance.
-- John

[Thomas Matthews]

John Eskie wrote:

Lets say I want to make multiply classes as singletons. A singleton skeleton
would be with a static member variable of the instance and a GetInstance
function.
Currently I have this functionality in all the classes where I need it but
I'd like to use templates or some other language construct so I can remove
the duplicated code.
A small example of what I'd like to do:

Singleton class functionality:
T *instance;
T *GetInstance();
...
class A
{
...implements the above
int varA;
};

Class B
{
... also implements singleton
double varB;
};

Thanks in advance.
-- John

Looks like the difference between class A and Class B [sic]
is the type of the member variable. If all stays the same
except the type, consider using templates.

template <class VarType>
class C
{
VarType varC;
};

As far as the Singleton goes, you could either make it
as a template or have the classes inherit from it.

--
Thomas Matthews

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