re = /\[(url=https:\/\/www\.translatum\.gr.*?)\[\/url]/m
str = 'Test aetejklkj fa jklkj dsdfs [url=https://www.translatum.gr/forum/index.php?topic=989146.0]telerobotically -> τηλερομποτικά, τηλερομποτικώς[/url] fskjlkj
Gfdsklkj fjgkjkl klkjdass
[url=https://www.in.gr/]in.gr | Όλες οι ειδήσεις - Ολοκληρωμένη κάλυψη ειδήσεων[/url] Gfdsklkj fjgkjkl klkjdass Gfdsklkj fjgkjkl klkjdass Gfdsklkj fjgkjkl klkjdass Gfdsklkj fjgkjkl klkjdass Gfdsklkj fjgkjkl klkjdass
Gfdsklkj fjgkjkl klkjdassGfdsklkj fjgkjkl klkjdassGfdsklkj fjgkjkl klkjdass Gfdsklkj fjgkjkl klkjdassGfdsklkj fjgkjkl klkjdassGfdsklkj fjgkjkl klkjdass '
subst = '[i\\1[/iurl]'
result = str.gsub(re, subst)
# Print the result of the substitution
puts result
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html