pry (1)

pry [--version] [--exec] [--no-pager] [--no-history] [--no-color] [-f] [--no-plugins] [--installed-plugins] [--simple-prompt] [--require file] [-I] [--context] [--help]

Pry is a powerful alternative to the standard IRB shell for Ruby. It is written from scratch to provide a number of advanced features.

http://pry.github.com/

-v --version

Prints the version of Pry.

-e --exec

Executes argument in context before the session starts.

--no-pager

Disable pager for long output.

--no-history

Disable history loading.

--no-color

Disable syntax highlighting for session.

-f

Prevent loading of ~/.pryrc for session.

--no-plugins

Suppress loading of plugins.

--installed-plugins

List installed plugins.

--simple-prompt

Enable simple prompt mode (eg, >>).

-r --require

Require a ruby script at startup.

-I

Add a path to the $LOAD_PATH

-c --context

Start the session in the specified context. Equivalent to context.pry in a session.

~/.pryrc Personal pry initialization

Basic Usage

$ pry
[1] pry(main)>4 + 5
=> 9
[2] pry(main)> def hello_world
[2] pry(main)*   puts "Hello, World!"
[2] pry(main)* end
=> nil
[3] pry(main)> hello_world
Hello, World!
=> nil

Command Line Interaction

Prefix any command you want your shell to execute with a period and pry will return the results from your shell.

• [1] pry(main)> .date
  Fri Nov 11 09:52:07 EST 2011
  

On the command line enter shell-mode to incorporate the current working directory into the Pry prompt.

• pry(main)> shell-mode
  pry main:/Users/john/ruby/projects/pry $ .cd ..
  pry main:/Users/john/ruby/projects $ .cd ~
  pry main:/Users/john $ .pwd
  /Users/john
  pry main:/Users/john $ shell-mode
  pry(main)>
  

State Navigation

The cd command is used to move into a new object (or scope) inside a Pry session. When inside the new scope it becomes the self for the session and all commands and methods will operate on this new self.

• pry(main)> self
  => main
  pry(main)> cd Pry
  pry(Pry):1> self
  => Pry
  pry(Pry):1> cd ..
  pry(main)>
  

The ls command is essentially a unified wrapper to a number of Ruby\'s introspection mechanisms, including (but not limited to) the following methods: methods, instance_variables, constants, local_variables, instance_methods, class_variables and all the various permutations thereof.

By default typing ls will return a list of just the local and instance variables available in the current context.

*

The -M option selects public instance methods (if available).

*

The -m option selects public methods.

*

The -c option selects constants.

*

The -i option select just instance variables.

*

The -l option selects just local variables.

*

The -s option modifies the -c and -m and -M options to go up the superclass chain (excluding Object).

*

The --grep REGEX prunes the list to items that match the regex.

Source Browsing

Simply typing show-method method_name will pull the source for the method and display it with syntax highlighting. You can also look up the source for multiple methods at the same time, by typing show-method method1 method2. As a convenience, Pry looks up both instance methods and class methods using this syntax, with priority given to instance methods.

• pry(Pry):1> show-method rep
  
  From: /Users/john/ruby/projects/pry/lib/pry/pry_instance.rb @ line 191:
  Number of lines: 6
  
  def rep(target=TOPLEVEL_BINDING)
    target = Pry.binding_for(target)
    result = re(target)
  
    show_result(result) if should_print?
  end
  

Pry is primarily the work of John Mair (banisterfiend)