module IRB class << (MagicFile = Object.new) # see parser_magic_comment in parse.y ENCODING_SPEC_RE = %r"coding\s*[=:]\s*([[:alnum:]\-_]+)" def open(path) io = File.open(path, 'rb') line = io.gets line = io.gets if line[0,2] == "#!" encoding = detect_encoding(line) encoding ||= default_src_encoding io.rewind io.set_encoding(encoding, nil) if block_given? begin return (yield io) ensure io.close end else return io end end private def detect_encoding(line) return unless line[0] == ?# line = line[1..-1] line = $1 if line[/-\*-\s*(.*?)\s*-*-$/] return nil unless ENCODING_SPEC_RE =~ line encoding = $1 return encoding.sub(/-(?:mac|dos|unix)/i, '') end end end