How do I remove all characters in a string until a substring is matched, in Ruby?

Question

Say I have a string: Hey what\'s up @dude, @how\'s it going?

I\'d like to remove all the characters before@how\'s.

Answer 1

or with the regex:

str = "Hey what's up @dude, @how's it going?"
str.gsub!(/.*?(?=@how)/im, "") #=> "@how's it going?"

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