ruby bytecode convert

#!/usr/bin/env ruby
# encoding: UTF-8

# info: compile ruby code in file.rb into bytecode and save it compressed as file.rbo
#       or load bytecode from compressed file.rbo and run it when an .rbo file is the input
# usage: script file.rb
#        script file.rbo
# requirements: ruby version >= 1.9

require 'zlib'


# check ruby version
(puts "error: minimum ruby version of 1.9"; exit 1) if RUBY_VERSION < "1.9.0"

# check file argument
(puts "error: file argument missing (ruby source file.rb or bytecode compiled file.rbo)"; exit 1) if ARGV.size < 1

# get file name
myfile = ARGV[0]

# file exists?
(puts "error: file #{myfile} does not exist"; exit 1) if not File.exist? myfile

# get file extension
myext = myfile.scan(/\.[^\.]*$/)[0]


# file is bytecode or plain source?
if    myext == ".rb"
    code = RubyVM::InstructionSequence.compile_file(myfile).to_a
    File.write("#{myfile}o", Zlib::Deflate.deflate(Marshal.dump(code)))

elsif myext == ".rbo"
    code = Marshal.restore((Zlib::Inflate.inflate(File.read(myfile))))
    RubyVM::InstructionSequence.load(code).eval

else
    puts "error: file type must be a ruby source file.rb or a ruby compiled bytecode file.rbo"
    exit 1
end