gistfile1.txt

# Ruby
File.open("homepages.csv", "w") { |f| 
    f.write Restaurant.active.delete_if { |r| 
        r.homepage.empty?
    }.map { |r| 
        [r.id, r.name, r.homepage].join(";") 
    }.join("\n") 
}

# Haskell (untested)
writeFile "homepages.csv" join "\n" map (\x -> join ";" [x.id, x.name, x.homepage]) filter (\x -> length x.homepage > 0) restaurants