ruby regex match from end of string

Question

I've read somewhere today that regex tag in SO gets most "give me ze code" type questions, so I was cautious in asking... I tried, but if this is a duplicate please let me know so I can delete.

[First]sometext[Second]

I would like to use Regex in Ruby to return value between second []:

Second

I so far have:

(?<=\[)(.*)(?=\])

which returns

First]sometext[Second

\[.*?(\[)

this grouping will return

[First]sometext[

so I've been struggling to somehow mix the two but no luck.. hope someone can help.

The closest reference I can find in SO was searched with "match second or nth occurence in regex" which I couldn't get it to work on my issue.

my workaround was to use gsub to replace the [First] with "" to the initial string with:

\[(.*?)\]

and then do another match.. but I would like know how it can be done with on regex usage.

Answer 1

> s = "ipsum[First]sometext[Second]lorem"
=> "ipsum[First]sometext[Second]lorem"
> s =~ /\[.*?\].*?\[(.*?)\]/
=> 5
> $1
=> "Second"

Answer 2

Why not use a greedy search at the beginning .* so capture as much as possible?

^.*\[(.*?)\]

Demo

You could then make it un-greedy (to capture only the stuff in the first [...] block) by appending ? as ^.*?.