Why Am I Getting the Error "Missing Terminating ] for Character Class"?
I Want to Cut a String with Brackets Using Sed. How to Avoid an Error If I Want to Drop a String with [? for Example: $ Echo '[Om/Mystring' | Grep -oP '(?
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I want to cut a string with brackets using sed.
How to avoid an error if I want to drop a string with [?
For example:
$ echo '[Om/mystring' | grep -oP '(?<=[Om\\)\w+'
grep: missing terminating ] for character class
2 Answers
As the error missing terminating ] for character class already says, the problem here has to do with [, which you need to escape. Otherwise, it is understood as a character class by grep.
Also, you are saying //, while you want to use / instead of \ according to your input.
All together, this prints a set of words after [Om/:
$ echo '[Om/mystring' | \grep -oP '(?<=\[Om\/)\w+'
mystring
You are getting the error because [ is a special character in regular expression syntax, introducing a character class. To be treated as a string literal, it must be escaped i.e. \[
If you just want to remove the [Om/ prefix, then it's simpler sed if you use a delimiter that doesn't appear in the pattern:
$ echo '[Om/mystring' | sed 's;\[Om/;;'
mystring
Sarah Jenkins is a veteran tech journalist with over 12 years of experience covering artificial intelligence, mobile innovations, and digital ethics. Her insights have appeared in leading technology publications worldwide.
