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# Duane Johnson's Interactive Ruby Configuration File (~/.irbrc)
#
# Just put this file in ~/.irbrc and your irb experience will be much better!

# Include tab-completion in irb
require 'irb/completion'

# Modify the prompt so it looks nice and tidy. Taken from Programming Ruby 2.
IRB.conf[:IRB_RC] = proc do |conf|
  leader = " " * conf.irb_name.length
  conf.prompt_i = "#{conf.irb_name} --> "
  conf.prompt_s = leader + ' \-" '
  conf.prompt_c = leader + ' \-+ '
  conf.return_format = leader + " ==> %s\n\n"
  puts "Welcome to interactive ruby!"
end

# Load and save each command in irb so we don't have to re-type stuff.  Taken from ctran.
# http://snipplr.com/view/1026/my-irbrc/
HISTFILE = "~/.irb_history"
MAXHISTSIZE = 100

begin
  if defined? Readline::HISTORY
    histfile = File::expand_path( HISTFILE )
    if File::exists?( histfile )
      lines = IO::readlines( histfile ).collect {|line| line.chomp}
      puts "Read %d saved history commands from %s." %
        [ lines.nitems, histfile ] if $DEBUG || $VERBOSE
      Readline::HISTORY.push( *lines )
    else
      puts "History file '%s' was empty or non-existant." %
        histfile if $DEBUG || $VERBOSE
    end

    Kernel::at_exit {
      lines = Readline::HISTORY.to_a.reverse.uniq.reverse
      lines = lines[ -MAXHISTSIZE, MAXHISTSIZE ] if lines.nitems > MAXHISTSIZE
      $stderr.puts "Saving %d history lines to %s." %
        [ lines.length, histfile ] if $VERBOSE || $DEBUG
      File::open( histfile, File::WRONLY|File::CREAT|File::TRUNC ) {|ofh|
  lines.each {|line| ofh.puts line }
      }
    }
  end
end

# Let's you use the "ri" command inside irb. Taken from Programming Ruby 2.
def ri(*names)
  system(%{ri #{names.map { |name| name.to_s }.join(" ")}})
end