size_type copy(charT* s, size_type n, size_type pos = 0) const;
Let 
rlen be the smaller of 
n and 
size() - pos.Throws: 
out_of_range
if
pos > size(). Requires: 
[s, s + rlen) is a valid range
. Effects: 
Equivalent to 
traits::copy(s, data() + pos, rlen).  [
 Note: This does not terminate 
s with a null object
. —
 end note  ]