https://www.youtube.com/watch?v=BJ0uHhBkzOQ

First example:

  type -a <something>

to discover what <something> is (or if it exists on your system)

They are shell-specific, yes. Fish also has it built-in.

Try man -a {pushd,popd} you can also use the man -k flag to find manpages, and see man man (or man --help) for more flags.

zsh also has them.

Another neat way of wrapping code in pushd/popd is to use a subshell.

    (cd $dir
       do-stuff
    )

Oilshell ( https://www.oilshell.org/ ) has support for code blocks so you can:

    cd /tmp {
      do-stuff
    }

They are bash built-ins. They are documented in bash's man page.

can also use `help pushd` to get manual only for that command ('help' is like 'man' for built-ins)

This is what I needed. None of the man pages showed information on the bash functions. 'help' did the job.

Ironically, 'man help' yields no results.

That's because `help` is also builtin. It's listed under "SHELL BUILTIN COMMANDS" in `man bash 1` (or use the non-obvious `help help`)

Get docs for shell builtins with help. Eg: `help pushd`