linux Terminal 能出多少提示上的花招

1

$ cpan perl-doc

...

Warning: Cannot install perl-doc, don't know what it is.

Try the command

i /perl-doc/

to find objects with matching identifiers.

$ i /perl-doc

The program 'i' is currently not installed. You can install it by typing:

sudo apt-get install iprint

$

问题：你说这玩意，怎么提示出来的

2

wayne@ubuntu:~/Downloads/lxr-1.2.0$ cpanm

The program 'cpanm' is currently not installed. You can install it by typing:

sudo apt-get install cpanminus

wayne@ubuntu:~/Downloads/lxr-1.2.0$

好奇：如果都能这样提示的话，那也太方便了啊，我喜欢！