clone method
The clone() method of the Response interface creates a clone of a
response object, identical in every way, but stored in a different
variable.
Like the underlying ReadableStream.tee api,
the Response.body of a cloned Response
will signal backpressure at the rate of the faster consumer of the two
bodies,
and unread data is enqueued internally on the slower consumed body
without any limit or backpressure.
Backpressure refers to the mechanism by which the streaming consumer of
data
(in this case, the code that reads the body)
slows down the producer of data (such as the TCP server)
so as not to load large amounts of data in memory
that is waiting to be used by the application.
If only one cloned branch is consumed, then the entire body will be
buffered in memory.
Therefore, clone() is one way to read a response twice in sequence,
but you should not use it to read very large bodies
in parallel at different speeds.
clone() throws a TypeError if the response body has already been used.
In fact, the main reason clone() exists is to allow multiple uses of
body objects (when they are one-use only.)
Implementation
external Response clone();