eshell-as-subcommand
eshell-as-subcommand is a Lisp macro in `esh-cmd.el
'.
(eshell-as-subcommand COMMAND)
Execute COMMAND using a temp buffer.
This is used so that certain Lisp commands, such as `cd', when
executed in a subshell, do not disturb the environment of the main
Eshell buffer.