watch out for those macros.. "macros are evil !"

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macros are evil !

i want to set an item text in a listview control representing a date
ListView_SetItemText(hWnd, iIndex, 1, log.GetTimeString().GetBuffer(0));

the log object is like this:
class CLog : public CObject
{

...
CString GetDateString() { return m_datetime.Format(_T("%d/%m/%Y")); }
CString GetTimeString() { return m_datetime.Format(_T("%H:%M:%S")); }

...

}

ListView_SetItemText(hWnd, iIndex, 1, log.GetTimeString().GetBuffer(0));
is bad because the CString object returned by the GetTimeString is temporary (and valid only in that line) but the ListView_SetItemtext is a macro !
looking inside it, it looks like this:

#define ListView_SetItemText(hwndLV, i, iSubItem_, pszText_) { LV_ITEM _ms_lvi;_ms_lvi.iSubItem = iSubItem_;_ms_lvi.pszText = pszText_;SNDMSG((hwndLV), LVM_SETITEMTEXT, (WPARAM)(i), (LPARAM)(LV_ITEM *)&_ms_lvi);}
so once the buffer is set to _ms_lvi.pszText the CString object is destroyed and the SNDMSG will send an invalid buffer

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