/usr/bin/irb

Usage:  irb.rb [options] [programfile] [arguments]
  -f                Suppress read of ~/.irbrc
  -d                Set $DEBUG to true (same as `ruby -d')
  -r load-module    Same as `ruby -r'
  -I path           Specify $LOAD_PATH directory
  -U                Same as `ruby -U`
  -E enc            Same as `ruby -E`
  -w                Same as `ruby -w`
  -W[level=2]       Same as `ruby -W`
  --context-mode n  Set n[0-4] to method to create Binding Object,
                    when new workspace was created
  --extra-doc-dir   Add an extra doc dir for the doc dialog
  --echo            Show result (default)
  --noecho          Don't show result
  --echo-on-assignment
                    Show result on assignment
  --noecho-on-assignment
                    Don't show result on assignment
  --truncate-echo-on-assignment
                    Show truncated result on assignment (default)
  --inspect         Use `inspect' for output
  --noinspect       Don't use inspect for output
  --multiline       Use multiline editor module
  --nomultiline     Don't use multiline editor module
  --singleline      Use singleline editor module
  --nosingleline    Don't use singleline editor module
  --colorize        Use colorization
  --nocolorize      Don't use colorization
  --autocomplete    Use autocompletion
  --noautocomplete  Don't use autocompletion
  --prompt prompt-mode/--prompt-mode prompt-mode
                    Switch prompt mode. Pre-defined prompt modes are
                    `default', `simple', `xmp' and `inf-ruby'
  --inf-ruby-mode   Use prompt appropriate for inf-ruby-mode on emacs.
                    Suppresses --multiline and --singleline.
  --sample-book-mode/--simple-prompt
                    Simple prompt mode
  --noprompt        No prompt mode
  --single-irb      Share self with sub-irb.
  --tracer          Display trace for each execution of commands.
  --back-trace-limit n
                    Display backtrace top n and tail n. The default
                    value is 16.
  --verbose         Show details
  --noverbose       Don't show details
  -v, --version	    Print the version of irb
  -h, --help        Print help
  --                Separate options of irb from the list of command-line args