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regexperlsedmultilineprefix

Perl: Multiline match + Adding prefix to all matched lines

I'm a Perl beginner. I usually use "sed" for pattern substitution, but as I need to comment out some multiline sections in a huge file, I thought of using Perl as being more powerful in multiline search.

Pattern Sample:

word1 {
    do not care1
    do not care2
    ...
} word2

Intended Output:

#word1 {
#    do not care1
#    do not care2
#    ...
#} word2

I found very useful Q&As on perl multiline matching, but I couldn't find any good/compact/easy solution to add prefix to ALL the matched lines (not just the first line).

For now, this is the code I wrote:

perl -0777 -pe 's/(word1\s*{[^}]*\s*}\s*word2\s.*)/#$1/gm'

But unfortunately it can't add the prefix (#) to all the matched lines as below:

#word1 {
    do not care1
    do not care2
    ...
} word2

Can you help please? I hope the code would still be in 1 line :)

Solution

  • Use the range operator:

    perl -pe 's/^/#/ if /word1\s*\{/ .. /\}\s*word2/'