Re: singleton initialization
{ Edits: quoted signature removed. -mod }
Alf P. Steinbach wrote:
* 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".
Ah, so this is the C++ way of doing it...I may be wrong, but in C at
least for plain old datatype, function static variable initialization
happens at compile time.
Fei
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