sidef-scripts/File/file_intersection.sf

#!/usr/bin/ruby

# Show the unique lines from file 1 that also exist in file 2.

var file1 = File(ARGV[0])
var file2 = File(ARGV[1])

func collect_lines(fh) {
    var list = Set()
    fh.each {|line|
        #list << line.words.last
        list << line
    }
    list
}

collect_lines(file1.open_r) & collect_lines(file2.open_r) -> each {|line|
    say line
}