module imports.bug846;

template ElemTypeOf( T )
{
    alias typeof(T.init[0]) ElemTypeOf;
}

template removeIf_( Elem, Pred )
{
    size_t fn( Elem[] buf, Pred pred )
    {
        void exch( size_t p1, size_t p2 )
        {
            Elem t  = buf[p1];
            buf[p1] = buf[p2];
            buf[p2] = t;
        }

        size_t cnt = 0;

        for( size_t pos = 0, len = buf.length; pos < len; ++pos )
        {
            if( pred( buf[pos] ) )
                ++cnt;
            else
                exch( pos, pos - cnt );
        }
        return buf.length - cnt;
    }
}

template removeIf( Buf, Pred )
{
    size_t removeIf( Buf buf, Pred pred )
    {
        return removeIf_!(ElemTypeOf!(Buf), Pred).fn( buf, pred );
    }
}
