#
#   irb/lc/help-message.rb - 
#   	$Release Version: 0.7.3$
#   	$Revision: 1.1.2.2 $
#   	$Date: 2001/06/01 15:26:47 $
#   	by Keiju ISHITSUKA(keiju@ishitsuka.com)
#
# --
#
#   
#
Usage:  irb.rb [options] [programfile] [arguments]
  -f		    suppress read ~/.irbrc 
  -m		    bc mode (load mathn, fraction or matrix are available)
  -d                set $DEBUG  to true (same as `ruby -d')
  -r load-module    same as `ruby -r'
  --inspect	    uses `inspect' for output (the default except bc mode)
  --noinspect	    doesn't uses inspect for output
  --readline	    uses Readline extension module
  --noreadline	    doesn't use Readline extension module
  --prompt prompt-mode
  --prompt-mode prompt-mode
		    switches prompt mode. Pre-defined prompt modes are
		    `default', `simple', `xmp' and `inf-ruby'
  --inf-ruby-mode   uses prompt appreciate for inf-ruby-mode on emacs. 
		    Suppresses --readline. 
  --simple-prompt   simple prompt mode
  --noprompt	    no prompt
  --tracer	    display trace for each execution of commands.
  --back-trace-limit n
		    displayes backtrace top n and tail n. The default
		    value is 16. 
  --irb_debug n	    sets internal debug level to n (It shouldn't be used)
  -v, --version	    prints the version of irb
