Bash capture groups

gistfile1.md

data:

locator: urn:asset:a1e2d1df-a741-6547-93e2-e84692c8e981
locator: urn:bbc:cps:asset:27510321

script:

#!/bin/bash

while read l
    do
        if [[ $l =~ [(\w*:\s\w*:\w*:)(\w*-.*)] ]]; then
            for i in "${BASH_REMATCH[@]}"
            do
                echo "Index: $i"
            done
            
            echo "${BASH_REMATCH[2]}"
        fi
done < data.txt

I think Crystal's matches because surrounding the whole regex in [ ] makes Bash treat the whole regex as a single character class, and because that class contains characters that could match anything it does match everything - so you're right, it is matching all the individual letters, but is capturing none of them.

Looking at mine again, of course I had forgotten that .+ matches spaces, so it matches all characters up until the final :, then captures everything up to the end.

Rubular uses PCRE and Bash uses ERE. There's subtle differences, but they're there.