README: refresh content, add more structurereadme-rework

* Wrap everything at 80 characters
* Delete outdated info with "future" plans
* Add better structure to the document

1 files changed, 290 insertions, 255 deletions

diff --git a/README.md b/README.md
index 88af86c6..61363285 100644
--- a/README.md
+++ b/README.md
@@ -16,8 +16,12 @@ Pry
 Introduction
 ------------
 
-Pry is a powerful runtime developer console and IRB alternative for Ruby. It
-provides a number of advanced features, including:
+Pry is a runtime developer console and IRB alternative with powerful
+introspection capabilities. Pry aims to be more than an IRB replacement. It is
+an attempt to bring REPL driven programming to the Ruby language.
+
+Key features
+------------
 
 * Source code browsing (including core C source with the pry-doc gem)
 * Documentation browsing
@@ -29,103 +33,117 @@ provides a number of advanced features, including:
 * Navigation around state (`cd`, `ls` and friends)
 * Runtime invocation (use Pry as a developer console or debugger)
 * Exotic object support (BasicObject instances, IClasses, ...)
-* A Powerful and flexible command system
+* A powerful and flexible command system
 * Ability to view and replay history
-* Many convenience commands inspired by IPython, Smalltalk and other advanced REPLs
-* A wide-range number of [plugins](https://github.com/pry/pry/wiki/Available-plugins) that provide remote sessions, full debugging functionality, and more.
+* Many convenience commands inspired by IPython, Smalltalk and other advanced
+  REPLs
+* A wide-range number of
+  [plugins](https://github.com/pry/pry/wiki/Available-plugins) that provide
+  remote sessions, full debugging functionality, and more.
+
+Installation
+------------
+
+### Bundler
+
+```ruby
+gem 'pry', '~> 0.12.2'
+```
+
+### Manual
+
+```sh
+gem install pry
+```
 
-Pry also aims to be more than an IRB replacement; it is an
-attempt to bring REPL driven programming to the Ruby language. It is
-currently not as powerful as tools like [SLIME](https://en.wikipedia.org/wiki/SLIME) for lisp, but that is the
-general direction Pry is heading.
+Overview
+--------
 
-Pry is also fairly flexible and allows significant user
+Pry is fairly flexible and allows significant user
 [customization](https://github.com/pry/pry/wiki/Customization-and-configuration)
-is trivial to set it to read from any object that has a `readline` method and write to any object that has a
-`puts` method - many other aspects of Pry are also configurable making
-it a good choice for implementing custom shells.
+is trivial to set it to read from any object that has a `readline` method and
+write to any object that has a `puts` method - many other aspects of Pry are
+also configurable making it a good choice for implementing custom shells.
 
-Pry comes with an executable so it can be invoked at the command line.  Just
+Pry comes with an executable so it can be invoked at the command line. Just
 enter `pry` to start. A `pryrc` file in `$XDG_CONFIG_HOME/pry/` or the user's
 home directory will be loaded if it exists. Type `pry --help` at the command
 line for more information.
 
-Try `gem install pry-doc` for additional documentation on Ruby Core
-methods. The additional docs are accessed through the `show-doc` and
-`show-method` commands.
-
-* Install the [gem](https://rubygems.org/gems/pry): `gem install pry`
-* Browse the comprehensive [documentation at the official Pry wiki](https://github.com/pry/pry/wiki)
-* Read the [YARD API documentation](http://www.rubydoc.info/github/pry/pry/)
-* See the [source code](https://github.com/pry/pry)
-
 ### Commands
 
-Nearly every piece of functionality in a Pry session is implemented as
-a command. Commands are not methods and must start at the beginning of a line, with no
-whitespace in between. Commands support a flexible syntax and allow
-'options' in the same way as shell commands, for example the following
-Pry command will show a list of all private instance methods (in
-scope) that begin with 'pa'
+Nearly every piece of functionality in a Pry session is implemented as a
+command. Commands are not methods and must start at the beginning of a line,
+with no whitespace in between. Commands support a flexible syntax and allow
+'options' in the same way as shell commands, for example the following Pry
+command will show a list of all private instance methods (in scope) that begin
+with 'pa'
 
-    pry(YARD::Parser::SourceParser):5> ls -Mp --grep ^pa
-    YARD::Parser::SourceParser#methods: parse  parser_class  parser_type  parser_type=  parser_type_for_filename
+```ruby
+pry(YARD::Parser::SourceParser):5> ls -Mp --grep ^pa
+YARD::Parser::SourceParser#methods: parse  parser_class  parser_type  parser_type=  parser_type_for_filename
+```
 
 ### Navigating around state
 
-Pry allows us to pop in and out of different scopes (objects) using
-the `cd` command. This enables us to explore the run-time view of a
-program or library. To view which variables and methods are available
-within a particular scope we use the versatile [ls command.](https://gist.github.com/c0fc686ef923c8b87715)
-
-Here we will begin Pry at top-level, then Pry on a class and then on
-an instance variable inside that class:
-
-    pry(main)> class Hello
-    pry(main)*   @x = 20
-    pry(main)* end
-    => 20
-    pry(main)> cd Hello
-    pry(Hello):1> ls -i
-    instance variables: @x
-    pry(Hello):1> cd @x
-    pry(20):2> self + 10
-    => 30
-    pry(20):2> cd ..
-    pry(Hello):1> cd ..
-    pry(main)> cd ..
-
-The number after the `:` in the pry prompt indicates the nesting
-level. To display more information about nesting, use the `nesting`
-command. E.g
-
-    pry("friend"):3> nesting
-    Nesting status:
-    0. main (Pry top level)
-    1. Hello
-    2. 100
-    3. "friend"
-    => nil
-
-We can then jump back to any of the previous nesting levels by using
-the `jump-to` command:
-
-    pry("friend"):3> jump-to 1
-    => 100
-    pry(Hello):1>
+Pry allows us to pop in and out of different scopes (objects) using the `cd`
+command. This enables us to explore the run-time view of a program or
+library. To view which variables and methods are available within a particular
+scope we use the versatile [ls
+command.](https://gist.github.com/c0fc686ef923c8b87715)
+
+Here we will begin Pry at top-level, then Pry on a class and then on an instance
+variable inside that class:
+
+```ruby
+pry(main)> class Hello
+pry(main)*   @x = 20
+pry(main)* end
+=> 20
+pry(main)> cd Hello
+pry(Hello):1> ls -i
+instance variables: @x
+pry(Hello):1> cd @x
+pry(20):2> self + 10
+=> 30
+pry(20):2> cd ..
+pry(Hello):1> cd ..
+pry(main)> cd ..
+```
+
+The number after the `:` in the pry prompt indicates the nesting level. To
+display more information about nesting, use the `nesting` command. E.g
+
+```ruby
+pry("friend"):3> nesting
+Nesting status:
+0. main (Pry top level)
+1. Hello
+2. 100
+3. "friend"
+=> nil
+```
+
+We can then jump back to any of the previous nesting levels by using the
+`jump-to` command:
+
+```ruby
+pry("friend"):3> jump-to 1
+=> 100
+pry(Hello):1>
+```
 
 ### Runtime invocation
 
-Pry can be invoked in the middle of a running program. It opens a Pry
-session at the point it's called and makes all program state at that
-point available. It can be invoked on any object using the
-`my_object.pry` syntax or on the current binding (or any binding)
-using `binding.pry`. The Pry session will then begin within the scope
-of the object (or binding). When the session ends the program continues with any
-modifications you made to it.
+Pry can be invoked in the middle of a running program. It opens a Pry session at
+the point it's called and makes all program state at that point available. It
+can be invoked on any object using the `my_object.pry` syntax or on the current
+binding (or any binding) using `binding.pry`. The Pry session will then begin
+within the scope of the object (or binding). When the session ends the program
+continues with any modifications you made to it.
 
-This functionality can be used for such things as: debugging,
-implementing developer consoles and applying hot patches.
+This functionality can be used for such things as: debugging, implementing
+developer consoles and applying hot patches.
 
 code:
 
@@ -148,246 +166,263 @@ puts "program resumes here."
 
 Pry session:
 
-    pry(main)> a.hello
-    hello world!
-    => nil
-    pry(main)> def a.goodbye
-    pry(main)*   puts "goodbye cruel world!"
-    pry(main)* end
-    => nil
-    pry(main)> a.goodbye
-    goodbye cruel world!
-    => nil
-    pry(main)> exit
-
-    program resumes here.
+```ruby
+pry(main)> a.hello
+hello world!
+=> nil
+pry(main)> def a.goodbye
+pry(main)*   puts "goodbye cruel world!"
+pry(main)* end
+=> nil
+pry(main)> a.goodbye
+goodbye cruel world!
+=> nil
+pry(main)> exit
+
+program resumes here.
+```
 
 ### Command Shell Integration
 
-A line of input that begins with a '.' will be forwarded to the
-command shell. This enables us to navigate the file system, spawn
-editors, and run git and rake directly from within Pry.
+A line of input that begins with a '.' will be forwarded to the command
+shell. This enables us to navigate the file system, spawn editors, and run git
+and rake directly from within Pry.
 
-Further, we can use the `shell-mode` command to incorporate the
-present working directory into the Pry prompt and bring in (limited at this stage, sorry) file name completion.
-We can also interpolate Ruby code directly into the shell by
+Further, we can use the `shell-mode` command to incorporate the present working
+directory into the Pry prompt and bring in (limited at this stage, sorry) file
+name completion.  We can also interpolate Ruby code directly into the shell by
 using the normal `#{}` string interpolation syntax.
 
 In the code below we're going to switch to `shell-mode` and edit the `pryrc`
 file. We'll then cat its contents and reload the file.
 
-    pry(main)> shell-mode
-    pry main:/home/john/ruby/projects/pry $ .cd ~
-    pry main:/home/john $ .emacsclient .pryrc
-    pry main:/home/john $ .cat .pryrc
-    def hello_world
-      puts "hello world!"
-    end
-    pry main:/home/john $ load ".pryrc"
-    => true
-    pry main:/home/john $ hello_world
-    hello world!
-
-We can also interpolate Ruby code into the shell. In the
-example below we use the shell command `cat` on a random file from the
-current directory and count the number of lines in that file with
-`wc`:
-
-    pry main:/home/john $ .cat #{Dir['*.*'].sample} | wc -l
-    44
+```ruby
+pry(main)> shell-mode
+pry main:/home/john/ruby/projects/pry $ .cd ~
+pry main:/home/john $ .emacsclient .pryrc
+pry main:/home/john $ .cat .pryrc
+def hello_world
+  puts "hello world!"
+end
+pry main:/home/john $ load ".pryrc"
+=> true
+pry main:/home/john $ hello_world
+hello world!
+```
 
-### Code Browsing
+We can also interpolate Ruby code into the shell. In the example below we use
+the shell command `cat` on a random file from the current directory and count
+the number of lines in that file with `wc`:
 
-You can browse method source code with the `show-method` command. Nearly all Ruby methods (and some C methods, with the pry-doc
-gem) can have their source viewed. Code that is longer than a page is
-sent through a pager (such as less), and all code is properly syntax
-highlighted (even C code).
+```ruby
+pry main:/home/john $ .cat #{Dir['*.*'].sample} | wc -l
+44
+```
 
-The `show-method` command accepts two syntaxes, the typical ri
-`Class#method` syntax and also simply the name of a method that's in
-scope. You can optionally pass the `-l` option to show-method to
-include line numbers in the output.
+### Code Browsing
 
-In the following example we will enter the `Pry` class, list the
-instance methods beginning with 're' and display the source code for the `rep` method:
+You can browse method source code with the `show-source` command. Nearly all
+Ruby methods (and some C methods, with the pry-doc gem) can have their source
+viewed. Code that is longer than a page is sent through a pager (such as less),
+and all code is properly syntax highlighted (even C code).
 
-    pry(main)> cd Pry
-    pry(Pry):1> ls -M --grep re
-    Pry#methods: re  readline  refresh  rep  repl  repl_epilogue  repl_prologue  retrieve_line
-    pry(Pry):1> show-method rep -l
+The `show-source` command accepts two syntaxes, the typical ri `Class#method`
+syntax and also simply the name of a method that's in scope. You can optionally
+pass the `-l` option to `show-source` to include line numbers in the output.
 
-    From: /home/john/ruby/projects/pry/lib/pry/pry_instance.rb:143
-    Number of lines: 6
+In the following example we will enter the `Pry` class, list the instance
+methods beginning with 're' and display the source code for the `rep` method:
 
-    143: def rep(target=TOPLEVEL_BINDING)
-    144:   target = Pry.binding_for(target)
-    145:   result = re(target)
-    146:
-    147:   show_result(result) if should_print?
-    148: end
+```ruby
+pry(main)> cd Pry
+pry(Pry):1> ls -M --grep re
+Pry#methods: re  readline  refresh  rep  repl  repl_epilogue  repl_prologue  retrieve_line
+pry(Pry):1> show-source rep -l
+
+From: /home/john/ruby/projects/pry/lib/pry/pry_instance.rb:143
+Number of lines: 6
+
+143: def rep(target=TOPLEVEL_BINDING)
+144:   target = Pry.binding_for(target)
+145:   result = re(target)
+146:
+147:   show_result(result) if should_print?
+148: end
+```
 
 Note that we can also view C methods (from Ruby Core) using the
 `pry-doc` plugin; we also show off the alternate syntax for
-`show-method`:
-
-    pry(main)> show-method Array#select
-
-    From: array.c in Ruby Core (C Method):
-    Number of lines: 15
-
-    static VALUE
-    rb_ary_select(VALUE ary)
-    {
-        VALUE result;
-        long i;
+`show-source`:
 
-        RETURN_ENUMERATOR(ary, 0, 0);
-        result = rb_ary_new2(RARRAY_LEN(ary));
-        for (i = 0; i < RARRAY_LEN(ary); i++) {
-            if (RTEST(rb_yield(RARRAY_PTR(ary)[i]))) {
-                rb_ary_push(result, rb_ary_elt(ary, i));
-            }
+```ruby
+pry(main)> show-source Array#select
+
+From: array.c in Ruby Core (C Method):
+Number of lines: 15
+
+static VALUE
+rb_ary_select(VALUE ary)
+{
+    VALUE result;
+    long i;
+
+    RETURN_ENUMERATOR(ary, 0, 0);
+    result = rb_ary_new2(RARRAY_LEN(ary));
+    for (i = 0; i < RARRAY_LEN(ary); i++) {
+        if (RTEST(rb_yield(RARRAY_PTR(ary)[i]))) {
+            rb_ary_push(result, rb_ary_elt(ary, i));
         }
-        return result;
     }
+    return result;
+}
+```
 
 ### Documentation Browsing
 
-One use-case for Pry is to explore a program at run-time by `cd`-ing
-in and out of objects and viewing and invoking methods. In the course
-of exploring it may be useful to read the documentation for a
-specific method that you come across. Like `show-method` the `show-doc` command supports
-two syntaxes - the normal `ri` syntax as well as accepting the name of
-any method that is currently in scope.
-
-The Pry documentation system does not rely on pre-generated `rdoc` or
-`ri`, instead it grabs the comments directly above the method on
-demand. This results in speedier documentation retrieval and allows
-the Pry system to retrieve documentation for methods that would not be
-picked up by `rdoc`. Pry also has a basic understanding of both the
-rdoc and yard formats and will attempt to syntax highlight the
-documentation appropriately.
-
-Nonetheless, the `ri` functionality is very good and
-has an advantage over Pry's system in that it allows documentation
-lookup for classes as well as methods. Pry therefore has good
-integration with  `ri` through the `ri` command. The syntax
-for the command is exactly as it would be in command-line -
+One use-case for Pry is to explore a program at run-time by `cd`-ing in and out
+of objects and viewing and invoking methods. In the course of exploring it may
+be useful to read the documentation for a specific method that you come
+across. Like `show-source` the `show-doc` command supports two syntaxes - the
+normal `ri` syntax as well as accepting the name of any method that is currently
+in scope.
+
+The Pry documentation system does not rely on pre-generated `rdoc` or `ri`,
+instead it grabs the comments directly above the method on demand. This results
+in speedier documentation retrieval and allows the Pry system to retrieve
+documentation for methods that would not be picked up by `rdoc`. Pry also has a
+basic understanding of both the rdoc and yard formats and will attempt to syntax
+highlight the documentation appropriately.
+
+Nonetheless, the `ri` functionality is very good and has an advantage over Pry's
+system in that it allows documentation lookup for classes as well as
+methods. Pry therefore has good integration with `ri` through the `ri`
+command. The syntax for the command is exactly as it would be in command-line -
 so it is not necessary to quote strings.
 
-In our example we will enter the `Gem` class and view the
-documentation for the `try_activate` method:
+In our example we will enter the `Gem` class and view the documentation for the
+`try_activate` method:
 
-    pry(main)> cd Gem
-    pry(Gem):1> show-doc try_activate
+```ruby
+pry(main)> cd Gem
+pry(Gem):1> show-doc try_activate
 
-    From: /Users/john/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems.rb:201
-    Number of lines: 3
+From: /Users/john/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems.rb:201
+Number of lines: 3
 
-    Try to activate a gem containing path. Returns true if
-    activation succeeded or wasn't needed because it was already
-    activated. Returns false if it can't find the path in a gem.
-    pry(Gem):1>
+Try to activate a gem containing path. Returns true if
+activation succeeded or wasn't needed because it was already
+activated. Returns false if it can't find the path in a gem.
+pry(Gem):1>
+```
 
 We can also use `ri` in the normal way:
 
-    pry(main) ri Array#each
-    ----------------------------------------------------------- Array#each
-         array.each {|item| block }   ->   array
-    ------------------------------------------------------------------------
-         Calls _block_ once for each element in _self_, passing that element
-         as a parameter.
+```ruby
+pry(main) ri Array#each
+----------------------------------------------------------- Array#each
+     array.each {|item| block }   ->   array
+------------------------------------------------------------------------
+     Calls _block_ once for each element in _self_, passing that element
+     as a parameter.
 
-            a = [ "a", "b", "c" ]
-            a.each {|x| print x, " -- " }
+        a = [ "a", "b", "c" ]
+        a.each {|x| print x, " -- " }
 
-         produces:
+     produces:
 
-            a -- b -- c --
+        a -- b -- c --
+```
 
 ### Gist integration
 
-If the `gist` gem is installed then method source or documentation can be gisted to GitHub with the
-`gist` command.  The `gist` command is capable of gisting [almost any REPL content](https://gist.github.com/cae143e4533416529726), including methods, documentation,
-input expressions, command source, and so on. In the example below we will gist the C source
-code for the `Symbol#to_proc` method to GitHub:
+If the `gist` gem is installed then method source or documentation can be gisted
+to GitHub with the `gist` command.  The `gist` command is capable of gisting
+[almost any REPL content](https://gist.github.com/cae143e4533416529726),
+including methods, documentation, input expressions, command source, and so
+on. In the example below we will gist the C source code for the `Symbol#to_proc`
+method to GitHub:
 
-    pry(main)> gist -m Symbol#to_proc
-    Gist created at https://gist.github.com/5332c38afc46d902ce46 and added to clipboard.
-    pry(main)>
+```ruby
+pry(main)> gist -m Symbol#to_proc
+Gist created at https://gist.github.com/5332c38afc46d902ce46 and added to clipboard.
+pry(main)>
+```
 
-You can see the actual gist generated here: [https://gist.github.com/5332c38afc46d902ce46](https://gist.github.com/5332c38afc46d902ce46)
+You can see the actual gist generated here:
+[https://gist.github.com/5332c38afc46d902ce46](https://gist.github.com/5332c38afc46d902ce46)
 
 ### Edit methods
 
-You can use `edit Class#method` or `edit my_method`
-(if the method is in scope) to open a method for editing directly in
-your favorite editor. Pry has knowledge of a few different editors and
-will attempt to open the file at the line the method is defined.
+You can use `edit Class#method` or `edit my_method` (if the method is in scope)
+to open a method for editing directly in your favorite editor. Pry has knowledge
+of a few different editors and will attempt to open the file at the line the
+method is defined.
 
 You can set the editor to use by assigning to the `Pry.editor`
-accessor. `Pry.editor` will default to `$EDITOR` or failing that will
-use `nano` as the backup default. The file that is edited will be
-automatically reloaded after exiting the editor - reloading can be
-suppressed by passing the `--no-reload` option to `edit`
+accessor. `Pry.editor` will default to `$EDITOR` or failing that will use `nano`
+as the backup default. The file that is edited will be automatically reloaded
+after exiting the editor - reloading can be suppressed by passing the
+`--no-reload` option to `edit`
 
-In the example below we will set our default editor to "emacsclient"
-and open the `Pry#repl` method for editing:
+In the example below we will set our default editor to "emacsclient" and open
+the `Pry#repl` method for editing:
 
-    pry(main)> Pry.editor = "emacsclient"
-    pry(main)> edit Pry#repl
+```ruby
+pry(main)> Pry.editor = "emacsclient"
+pry(main)> edit Pry#repl
+```
 
 ### Live Help System
 
-Many other commands are available in Pry; to see the full list type
-`help` at the prompt. A short description of each command is provided
-with basic instructions for use; some commands have a more extensive
-help that can be accessed via typing `command_name --help`. A command
-will typically say in its description if the `--help` option is
-available.
+Many other commands are available in Pry; to see the full list type `help` at
+the prompt. A short description of each command is provided with basic
+instructions for use; some commands have a more extensive help that can be
+accessed via typing `command_name --help`. A command will typically say in its
+description if the `--help` option is available.
 
 ### Use Pry as your Rails Console
 
-The recommended way to use Pry as your Rails console is to add
-[the `pry-rails` gem](https://github.com/rweng/pry-rails) to
-your Gemfile. This replaces the default console with Pry, in
-addition to loading the Rails console helpers and adding some
-useful Rails-specific commands.
+The recommended way to use Pry as your Rails console is to add [the `pry-rails`
+gem](https://github.com/rweng/pry-rails) to your Gemfile. This replaces the
+default console with Pry, in addition to loading the Rails console helpers and
+adding some useful Rails-specific commands.
 
-If you don't want to change your Gemfile, you can still run a Pry
-console in your app's environment using Pry's `-r` flag:
+If you don't want to change your Gemfile, you can still run a Pry console in
+your app's environment using Pry's `-r` flag:
 
-    pry -r ./config/environment
+```sh
+pry -r ./config/environment
+```
 
-Also check out the [wiki](https://github.com/pry/pry/wiki/Setting-up-Rails-or-Heroku-to-use-Pry)
+Also check out the
+[wiki](https://github.com/pry/pry/wiki/Setting-up-Rails-or-Heroku-to-use-Pry)
 for more information about integrating Pry with Rails.
 
-### Limitations:
+### Syntax Highlighting
 
-* Tab completion is currently a bit broken/limited this will have a
-  major overhaul in a future version.
+Syntax highlighting is on by default in Pry. If you want to change the colors,
+check out the [pry-theme](https://github.com/kyrylo/pry-theme) gem.
 
-### Syntax Highlighting
+You can toggle the syntax highlighting on and off in a session by using the
+`toggle-color` command. Alternatively, you can turn it off permanently by
+putting the line `Pry.color = false` in your `pryrc` file.
 
-Syntax highlighting is on by default in Pry. If you want to change
-the colors, check out the [pry-theme](https://github.com/kyrylo/pry-theme)
-gem.
+Supported Rubies
+----------------
 
-You can toggle the syntax highlighting on and off in a session by
-using the `toggle-color` command. Alternatively, you can turn it off
-permanently by putting the line `Pry.color = false` in your `pryrc`
-file.
+* CRuby >= 1.9.3
+* JRuby >= 1.7
 
-### Future Directions
+Contact
+-------
 
-Many new features are planned such as:
+In case you have a problem, question or a bug report, feel free to:
 
-* Increase modularity (rely more on plugin system)
-* Much improved documentation system, better support for YARD
-* Better support for code and method reloading and saving code
-* Extended and more sophisticated command system, allowing piping
-between commands and running commands in background
+* ask a question on IRC (#pry on Freenode)
+* [file an issue](https://github.com/pry/pry/issues)
+* [tweet at us](https://twitter.com/pryruby)
 
-### Contact
+License
+-------
 
-Problems or questions? File an issue at [GitHub](https://github.com/pry/pry/issues).
+The project uses the MIT License. See LICENSE.md for details.