Are the rules for what I escape in a bracket different for what I do outside of brackets?
For example should I escape a ? inside a bracket? Is it /blah[^?]/ or /blah[^\?]/
Are the rules for brackets different than not, or should I be escaping both the same?
Are the rules for what I escape in a bracket different for what I do outside of brackets?
For example should I escape a ? inside a bracket? Is it /blah[^?]/ or /blah[^\?]/
Are the rules for brackets different than not, or should I be escaping both the same?
Share Improve this question edited May 15, 2012 at 5:45 nnnnnn 150k30 gold badges208 silver badges247 bronze badges asked May 15, 2012 at 2:16 qwertymkqwertymk 35.3k30 gold badges124 silver badges184 bronze badges 1- the title don't match with the real question – ajax333221 Commented May 15, 2012 at 3:22
1 Answer
Reset to default 32The only thing that needs to be escaped in brackets is a closing bracket, and a minus if it is not initial or final, and a hat if it is initial, AFAIK. And the backslash itself, obviously.
The reason is, these are the only characters with a special significance inside the brackets. A closing bracket ends the brackets, a mid-string minus indicates a range, and an initial hat negates the bracket class. Everything else should be literally interpreted. The backslash is the escape character, so you need a double backslash to match a literal backslash.