Close1
Implements ISO's close/1: closes the stream identified by the first argument (an alias or $stream(...) term, see IOPrimitiveUtils.ensuringArgumentIsChannel) and drops every alias, other than the reserved "current" one, under which it was reachable.
Throws
if the argument is unbound.
if it does not identify an open channel.
(stream_or_alias) if it is neither an atom nor a $stream(...) term.
Fails, rather than erroring, if the channel is already closed.