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I've been and come back now, but for anyone reading this the rules are quite varied there. Or at least the interpretation of them is quite varied!
As of January 5th (post 1st Jan rule change) there is no smoking in public buildings like airports and museums, but many restaurants, bars and cafes continue to allow smoking without any restrictions. Its quite a good balance allowing non smokers to find smoke free places quite easily and smokers to find the thick fog they thrive on!
Great city, we enjoyed it a lot.