"But, uh-oh, strings are immutable, so each of these append operations causes the entire multi-megabyte string to be copied." This is only true when the scope

"But, uh-oh, strings are immutable, so each of these append operations causes the entire multi-megabyte string to be copied." This is only true when the scope is limited to specific languages… I am pretty sure that the author is talking bare or low-level stuffs, but it would be better to mention some language scope…