WINEVENTPROC

Undocumented in source but is binding to Windows. You might be able to learn more by searching the web for its name.
extern (Windows) nothrow
static if(_WIN32_WINNT >= 0x500)
alias WINEVENTPROC = void function(HWINEVENTHOOK, DWORD, HWND, LONG, LONG, DWORD, DWORD)

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