--- File.basename(filename[, suffix])

    filename ΰָΥå³Ǥ֤ޤ⤷
     suffix ͿơĤ줬 filename 
    פʤ顢Τ֤ޤ

    :

      p File.basename("ruby/ruby.c")        #=> "ruby.c"
      p File.basename("ruby/ruby.c", ".c")  #=> "ruby"
      p File.basename("ruby/ruby.c", ".*")  #=> "ruby"
      p File.basename("ruby/ruby.exe", ".*")  #=> "ruby"

    File.dirname, File.extname ⻲ȡ

