[SOLVED] regex - brackets and parenthesis in character-class

Issue

I would like to match these characters: [ ] ( ) in a character class in a regex, how can I do that?

echo 'some text (some text in parenthesis) [some other in brackets]' | grep '[\[\]\(\)]'

This one doesn't match any character.

Solution

You can use it like this:

echo 'some text (some text in paranthesis) [some other in brackets]' |
grep -o '[][()]'

(
)
[
]

Please note that:

• If ] and [ are placed right after opening [ in a bracket expression then they are treated as literals ] or [.
• That may be an optional ^ at the first place for negation before ] or [
• You don't need to escape ( and ) inside a bracket expression.

Answered By - anubhava

Answer Checked By - Gilberto Lyons (WPSolving Admin)