.irbrc.rb

# Put this to ~/.irbrc (no extension)

require "rubygems"
require 'irb/completion'

ARGV.concat [ "--readline", "--prompt-mode", "simple" ]

# IRB & Readline hostory
module Readline
  module History
    LOG = "#{ENV['HOME']}/.irb-history"

    def self.write_log(line)
      File.open(LOG, 'ab') {|f| f << "#{line}\n" }
    end

    def self.start_session_log
      write_log("\n# session start: #{Time.now}\n\n")
      at_exit { write_log("\n# session stop: #{Time.now}\n") }
    end
  end

  alias :old_readline :readline
  def readline(*args)
    ln = old_readline(*args)
    begin
      History.write_log(ln)
    rescue
    end
    ln
  end
end

Readline::History.start_session_log

require 'irb/ext/save-history'
IRB.conf[:SAVE_HISTORY] = 100
IRB.conf[:HISTORY_FILE] = "#{ENV['HOME']}/.irb-save-history"

IRB.conf[:PROMPT_MODE] = :SIMPLE

# IRB configuration reloading

def IRB.reload
  load __FILE__
end


# Simple benchmarking
def time(times = 1)
  require 'benchmark'

  ret = nil
  Benchmark.bm { |x| x.report { times.times { ret = yield } } }
  ret
end

# Migration
def migrate(&block)
  ActiveRecord::Migration.instance_eval(&block)
end

# SQL query execution
def sql(query)
  ActiveRecord::Base.connection.select_all(query)
end