grep like search to gmail.

search_gmail.rb

#!/Users/Altech/.rvm/rubies/ruby-1.9.3-p194/bin/ruby
# -*- coding: utf-8 -*-

require 'gmail'
require 'nokogiri'
require 'colorize'
require 'pry'

gmail = Gmail.connect('takeno.sh',PASSWORD)

emails = gmail.mailbox('MailMagazine').emails

keyword = 'grep'

N = 20

emails.each do |email|
  msg = email.message.body.to_s.encode('utf-8','iso-2022-jp')
  i = msg.index(keyword)
  next if i.nil?
  quotation = msg[i-N..i-1]+msg[i,keyword.size].red+msg[i+keyword.size,N]
  subject = email.header.fields.detect{|i| i.name == "Subject"}.to_s
  puts subject.blue + "\t" + "...#{quotation}..."
end   

Hi, I ran this program April 4th, 2018 and get this error:

/usr/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in 'require': cannot load such file -- gmail (LoadError) from /usr/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in 'require' from search_gmail.rb:4:in '<main>'

I can also post on SO, but I figured I should let you know. Not sure if my version of ruby is outdated or what, but might be good to update! I'm excited to be able to search my e-mail with something like grep

Thanks!