Say I have a text file like this:
a;bc;d;{a;b;cd}
ab;cde;f;{ab;c;defg}
ab;{a;b;cd};cde;f
...
and I want to replace all the semicolons in curly brackets by comma. It will look like this after substitution:
a;bc;d;{a,b,cd}
ab;cde;f;{ab,c,defg}
ab;{a,b,cd};cde;f
...
How should I do it in shell command? sed, awk or whatever...
Perl to the rescue:
perl -pe 's/({.*?})/ $1 =~ s=;=,=gr /ge' input
The problem is your expected output is wrong:
a;b;cd a;b;cd
| |
V V
a,b,c,d ab,cd
Through perl which uses positive lookahead,
$ perl -pe 's/;(?=[^{}]*})/,/g' file
a;bc;d;{a,b,cd}
ab;cde;f;{ab,c,defg}
ab;{a,b,cd};cde;f
sed ':a; s/\(.*\)\({\)\([^;]*\)\(;\)\([^}]*}.*\)/\1\2\3,\5/;t a' file
put a label in the beginning and section off hold patterns and loops around until no more successful substitutions on each line (t a)
E.g.
a;bc;d;{a;b;cd}morestuff{bsdj;dsfkjl;sdkjl;kd}
ab;cde;f;{ab;c;defg}
ab;{a;b;cd};cde;f
Output:
a;bc;d;{a,b,cd}morestuff{bsdj,dsfkjl,sdkjl,kd}
ab;cde;f;{ab,c,defg}
ab;{a,b,cd};cde;f