Re: singleton initialization
* Fei Liu:
Eric wrote:
class CTestClass
{
public:
static CTestClass& instance()
{
static CTestClass* m_instance = new CTestClass;
This doesn't make sense. How can the compiler create this object at
compile time?
The object is created at run time.
Change this to:
static CTestClass& instance()
{
static CTestClass* m_instance;
if(!m_instance) m_instance = new CTestClass;
return m_instance;
}
This merely replicates the code generated by the compiler for the
original, but in a more verbose and possibly less efficient way.
See ?6.7/4, "is initialized the first time control passes through its
declaration".
Hth.,
- Alf, 16.05.2007 00:22
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