Boolean OR in sed regex

问题

I'm trying to replace all references of a package named boots in a configuration file.

The line format is add fast (package OR pkg) boots-(any-other-text), e.g.:

add fast package boots-2.3
add fast pkg boots-4.5

I want to replace it with:

add fast pkg boots-5.0

I've tried the following sed commands:

sed -e 's/add fast (pkg\|package) boots-.*/add yinst pkg boots-5.0/g'
sed -e 's/add fast [pkg\|package] boots-.*/add yinst pkg boots-5.0/g'

What's the right regex? I think I'm missing something in the boolean or (package or pkg) part.

回答1:

sed -e 's/add fast \(pkg\|package\) boots-.*/add yinst pkg boots-5.0/g'

You could always avoid the OR by doing it twice

sed 's/add fast pkg boots-.*/add yinst pkg boots-5.0/g
s/add fast package boots-.*/add yinst pkg boots-5.0/g'

回答2:

Use extended regex mode, and don't escape the |.

sed -E -e 's/add fast (pkg|package) boots-.*/add yinst pkg boots-5.0/g'

回答3:

You're mixing BRE's and ERE's either escape both () and | or none.

sed uses basic regular expressions by default, enabling use of extended regular expressions is implementation dependent, e.g. with BSD sed you use the -E switch, GNU sed has it documented as -r, but -E works as well.

回答4:

GNU (Linux):

1) Make following random strings

   cidr="192.168.1.12"
   cidr="192.168.1.12/32"
   cidr="192.168.1.12,8.8.8.8"

to blank

2) sed with -r for using the logical operators in GNU like @Thor mentioned, and -i to on the fly edit a file on match found

$ echo '<user id="1000" cidr="192.168.1.12">' > /tmp/1000.xml
$ sed -r -i \ 
  s/'cidr="192.168.1.12\/32"|cidr="192.168.1.12"|192.168.1.12,'/''/ /tmp/1000.xml

-r = GNU sed
-i = search / match/ edit the changes to the file on the fly

来源：https://stackoverflow.com/questions/14813145/boolean-or-in-sed-regex

标签

regex

sed

logical-operators