strange syntax in stl (gnu version)

[Ningyu Shi]

I saw something really wierld in g++ version of stl source.

void construct(pointer __p, const _Tp& __val) { ::new(__p)
_Tp(__val); }

anybody knows about the syntax new(__p) means? can new really take a
pointer as a parameter?

 

[Ian Collins]

I saw something really wierld in g++ version of stl source.

void construct(pointer __p, const _Tp& __val) { ::new(__p)
_Tp(__val); }

anybody knows about the syntax new(__p) means? can new really take a
pointer as a parameter?

Look up placement new.