[boost] #pragma once

From: Alberto Barbati (abarbati_at_[hidden])
Date: 2002-12-28 11:05:41

Hi Everybody,

I saw in a lot of boost header files the following lines:

#if _MSC_VER >= 1020
#pragma once
#endif

or even better:

#if _MSC_VER+0 >= 1020
#pragma once
#endif

But not only MS compilers have the pragma once, which is in my opinion 
very useful. Why don't we define a BOOST_HAS_PRAGMA_ONCE in the 
compiler-specific config headers? Then we could write:

#if BOOST_HAS_PRAGMA_ONCE
#pragma once
#endif

Alberto Barbati