how to replace a sed expression (change and print only matched line) with a perl expression?

Question

I am trying to move to perl (from sed). But how can I replace this sed expression with perl in a similarly short way?

sed -n '/patternmatch/s%stuff%changed%p' file

I need to search for a pattern, and only when the pattern is found, substitute "stuff" with "changed".

The only way I could do it was with an if statement which looks like this

perl -ne 'if ( /patternmatch/ ) { s%stuff%changed%; print }' file

Is it possible to do it as short as with sed? How?

PS: How to do it with python is here.

Answer 1

Use the modifier form of if:

perl -ne 's/stuff/changed/, print if /patternmatch/'

or, you can use and and or for flow control:

perl -ne '/patternmatch/ and s/stuff/changed/, print'

Answer 2

's/abc/xyz/'

user@unix:~$ echo 'abc' | sed      's/abc/xyz/'
xyz   

user@unix:~$ echo 'abc' | perl -pe 's/abc/xyz/'
xyz

user@unix:~$ echo 'abc' > file.txt && cat file.txt
abc

user@unix:~$ sed      's/abc/xyz/' file.txt
xyz   

user@unix:~$ perl -pe 's/abc/xyz/' file.txt
xyz

---

's/patternmatch/stuffchanged/'

user@unix:~$ echo 'patternmatch' | sed      's/patternmatch/stuffchanged/'
stuffchanged   

user@unix:~$ echo 'patternmatch' | perl -pe 's/patternmatch/stuffchanged/'
stuffchanged

user@unix:~$ echo 'patternmatch' > file.txt && cat file.txt
patternmatch

user@unix:~$ sed      's/patternmatch/stuffchanged/' file.txt
stuffchanged   

user@unix:~$ perl -pe 's/patternmatch/stuffchanged/' file.txt
stuffchanged