sed将此模式替换为null

Question

A string with this format

aaa,bbb,ccc,ddd,pattern:[[xxxxxxxxxxxx],[yyyyyyyyyyyyyyy]],eee,fff,pattern:[[eeeeeeeeee],[fffffffff]]

How can I use sed to replace pattern: [[ ???????????? ]] [[ ???????????? ]] with null

Example

sed s/pattern:[[ ????????? ]]//g

I tried sed s/pattern:\\[\\[\\([^]]*\\)\\]\\]//g but it does not work.

Answer 1

You can use perl as sed doesn't support non-greedy matching:

s='aaa,bbb,ccc,ddd,pattern:[[xxxxxxxxxxxx],[yyyyyyyyyyyyyyy]],eee,fff,pattern:[[eeeeeeeeee],[fffffffff]]'

perl -pe 's/pattern:\[\[.*?\]\]//g' <<< "$s"

aaa,bbb,ccc,ddd,,eee,fff,

Answer 2

Using this as a test file:

$ cat file
aaa,bbb,ccc,ddd,pattern:[[xxxxxxxxxxxx],[yyyyyyyyyyyyyyy]],eee,fff,pattern:[[eeeeeeeeee],[fffffffff]]

Using sed:

$ sed 's/\]\]/\n/g; s/pattern:\[\[[^\n]*\n//g; s/\n/]]/g' file
aaa,bbb,ccc,ddd,,eee,fff,

How it works

Because sed does not have non-greedy regular expressions, we have to use a trick:

• s/\\]\\]/\\n/g

  This replaces all occurrences of ]] with a newline.

• s/pattern:\\[\\[[^\\n]*\\n//g

  This replaces all occurrences of pattern:[[ followed by any non-newline characters, [^\\n]* , followed by a newline, \\n , with an empty string.

• s/\\n/]]/g

  If any newline characters, \\n , happen to remain, this changes them back to ]] .

Answer 3

With awk :

awk -v RS='pattern:\\[\\[|\\]\\]' 'NR%2' ORS= s1 file

• RS='pattern:\\\\[\\\\[|\\\\]\\\\]' - treating pattern:[[ and ]] as complex record separator (based on regex alternation group ...|... )

The output:

aaa,bbb,ccc,ddd,,eee,fff,

Answer 4

If you can guarantee that it always looks has sets of square brackets like

pattern:[[abc],[def],...,[stu],[vxy]] 

then you could do something like this:

sed 's/pattern:\[\{2\}[^]]*\(\],\[[^]]*\)*\]\{2\}//g'

That is a pattern starting with 2 '[' followed by anything that is not a closing bracket followed by optionally '],[' and anything that is not a closing bracket and finishing with ']]'

Update:

With the revised requirements to support the following 3 types of pattern:

• pattern:[[aaa],[bbb],...,[xxx],[yyy]]
• pattern:[[aaaaa]]
• pattern:[]

the solution is:

sed 's/pattern:\[\{1,2\}[^]]*\(\],\[[^]]*\)*\]\{1,2\}//g'

Answer 5

This might work for you (GNU sed):

sed 's/\[\[[^]]*\]\(,\[[^]]*\]\)*\]//g' file

The regexp follows the pattern (re Friedl):

sed 's/normal(special normal)*/replacement/g' file