Ruby の 定番対話ツール pry 徹底攻略 | 
Live help system
概要
Ruby の 定番対話ツール pry 徹底攻略
Live help system について
Live help system
pry の設計のひとつのゴールはセルフドキュメンテーションです。
そのためにも、 pry は REPL 内で利用する pry のほとんどすべての
ドキュメントを提供します。
Viewing a Pry method's documentation
Pry はただの Ruby のコードであり、ほとんどのドキュメントは
show-doc コマンドで参照可能です。
show-doc のドキュメントを取得する
[2] pry(main)> show-doc show-doc
From: /path/to/ruby/gems/2.1.0/gems/pry-0.10.1/lib/pry/commands/show_doc.rb
Number of lines: 15
Usage: show-doc [OPTIONS] [METH]
Aliases: ?
Show the documentation for a method or class. Tries instance methods first and
then methods by default.
show-doc hi_method # docs for hi_method
show-doc Pry # for Pry class
show-doc Pry -a # for all definitions of Pry class (all monkey patches)
-s, --super Select the 'super' method. Can be repeated to traverse the ancestors
-l, --line-numbers Show line numbers
-b, --base-one Show line numbers but start numbering at 1 (useful for `amend-line` and `play` commands)
-a, --all Show all definitions and monkeypatches of the module/class
-h, --help Show this message.
show-doc の alias である、 ? で Pry#prompt のドキュメントを取得する
[6] pry(main)> ? Pry#prompt
From: /path/to/ruby/gems/2.1.0/gems/pry-0.10.1/lib/pry/pry_instance.rb @ line 84:
Owner: Pry
Visibility: public
Signature: prompt()
Number of lines: 8
The current prompt.
This is the prompt at the top of the prompt stack.
example
self.prompt = Pry::SIMPLE_PROMPT
self.prompt # => Pry::SIMPLE_PROMPT
return [Array<Proc>] Current prompt.
Learning about Pry's configuration options
オプションのヘルプを確認
Live Help 機能は、 pry のオプション設定について覚えるのに便利です。（公式ドキュメント談）
しかし・・・
[21] pry("hoge"):2> ? Pry.config.editor
Error: No superclass found for #<Method: #<Pry::Config:0x3ff173dddb60 local_keys=['pry_debugger','pry_doc','has_pry_doc','hooks'] default=#<Pry::Config::Default:0x3ff173de70e8 local_keys=['gist','history'] default=nil>>.editor>
[23] pry("hoge"):2> _ex_.backtrace
=> ["(pry):6:in `__pry__'",
"/path/to/ruby/gems/2.0.0/gems/pry-0.10.1/lib/pry/pry_instance.rb:355:in `eval'",
"/path/to/ruby/gems/2.0.0/gems/pry-0.10.1/lib/pry/pry_instance.rb:355:in `evaluate_ruby'",
# 以下略
公式ドキュメントをそのまま試したらエラーになった。 
※念のため Windows + Cygwin 環境と Ubuntu 環境の双方で確認したが同じ。
参考までにソースコードの表示も試したがダメ
[25] pry(main)> $ Pry.config.editor
Error: No superclass found for #<Method: #<Pry::Config:0x300359410 local_keys=['pry_byebug','pry_doc','has_pry_doc','hooks'] default=#<Pry::Config::Default:0x3003598c0 local_keys=['gist','history'] default=nil>>.editor>
代替手段を探す
- 以下で、ソースコードは表示できた
[58] pry("hoge"):1> $ _pry_.editor
From: /path/to/.rbenv/versions/2.1.0-rc1/lib/ruby/gems/2.1.0/gems/pry-0.10.1/lib/pry/config/convenience.rb @ line 21:
Owner: Pry
Visibility: public
Number of lines: 1
define_method(reader) { config.public_send(name) }
- ドキュメントは・・・だめ
これって、公式ドキュメントを書いた当初はべた書き実装で、メソッドコメントが付いていたけど、
現在は define_method で動的定義しているからドキュメントがない、ってことだろうか？
Wiki の該当ページの最終更新日は 6 Feb 2013
[61] pry("hoge"):1> ? _pry_.editor
Error: No docs found for: _pry_.editor
バグではなく、ドキュメンテーションが追いついていない、といったところでしょうか？
とりあえず、今後記事化予定の
の内容が古くなければそちらでカバーできそうかな？
The help command (Pry command documentation)
Pry の command はメソッドではないため、他のメソッドのように簡単に show-doc で確認できません。
代わりに、 help command を利用します。
help で実行可能な全コマンドを表示します。
help <command name> で対象コマンドの詳細を表示します。
help
[9] pry(main)> help
Help
help Show a list of commands or information about a specific command.
Context
cd Move into a new context (object or scope).
find-method Recursively search for a method within a class/module or the current namespace.
ls Show the list of vars and methods in the current scope.
pry-backtrace Show the backtrace for the pry session.
raise-up Raise an exception out of the current pry instance.
reset Reset the repl to a clean state.
watch Watch the value of an expression and print a notification whenever it changes.
whereami Show code surrounding the current context.
wtf? Show the backtrace of the most recent exception.
Editing
/^\s*!\s*$/ Clear the input buffer.
amend-line Amend a line of input in multi-line mode.
edit Invoke the default editor on a file.
hist Show and replay readline history.
play Playback a string variable, method, line, or file as input.
show-input Show the contents of the input buffer for the current multi-line expression.
Introspection
ri View ri documentation.
show-doc Show the documentation for a method or class.
show-source Show the source for a method or class.
stat View method information and set _file_ and _dir_ locals.
Gems
[10] pry(main)> help
Help
help Show a list of commands or information about a specific command.
Context
cd Move into a new context (object or scope).
find-method Recursively search for a method within a class/module or the current namespace.
ls Show the list of vars and methods in the current scope.
pry-backtrace Show the backtrace for the pry session.
raise-up Raise an exception out of the current pry instance.
reset Reset the repl to a clean state.
watch Watch the value of an expression and print a notification whenever it changes.
whereami Show code surrounding the current context.
wtf? Show the backtrace of the most recent exception.
Editing
/^\s*!\s*$/ Clear the input buffer.
amend-line Amend a line of input in multi-line mode.
edit Invoke the default editor on a file.
hist Show and replay readline history.
play Playback a string variable, method, line, or file as input.
show-input Show the contents of the input buffer for the current multi-line expression.
Introspection
ri View ri documentation.
show-doc Show the documentation for a method or class.
show-source Show the source for a method or class.
stat View method information and set _file_ and _dir_ locals.
Gems
gem-cd Change working directory to specified gem's directory.
gem-install Install a gem and refresh the gem cache.
gem-list List and search installed gems.
gem-open Opens the working directory of the gem in your editor.
Commands
import-set Import a pry command set.
install-command Install a disabled command.
Aliases
!!! Alias for `exit-program`
!!@ Alias for `exit-all`
$ Alias for `show-source`
? Alias for `show-doc`
@ Alias for `whereami`
breakpoint Alias for `break`
breaks Alias for `breakpoints`
c Alias for `continue`
clipit Alias for `gist --clip`
f Alias for `finish`
file-mode Alias for `shell-mode`
history Alias for `hist`
n Alias for `next`
quit Alias for `exit`
quit-program Alias for `exit-program`
reload-method Alias for `reload-code`
s Alias for `step`
show-method Alias for `show-source`
Input and output
.<shell command> All text following a '.' is forwarded to the shell.
cat Show code from a file, pry's input buffer, or the last exception.
change-inspector Change the current inspector proc.
change-prompt Change the current prompt.
fix-indent Correct the indentation for contents of the input buffer
list-inspectors List the inspector procs available for use.
list-prompts List the prompts available for use.
save-file Export to a file using content from the repl.
shell-mode Toggle shell mode. bring in pwd prompt and file completion.
Misc
gist Upload code, docs, history to https://gist.github.com/.
pry-version Show pry version.
reload-code Reload the source file that contains the specified code object.
toggle-color Toggle syntax highlighting.
Navigating pry
!pry Start a pry session on current self.
disable-pry Stops all future calls to pry and exits the current session.
exit Pop the previous binding.
exit-all End the current pry session.
exit-program End the current program.
jump-to Jump to a binding further up the stack.
nesting Show nesting information.
switch-to Start a new subsession on a binding in the current stack.
Prompts
simple-prompt Toggle the simple prompt.
Pry-byebug (v2.0.0)
break Set or edit a breakpoint.
breakpoints List defined breakpoints.
continue Continue program execution and end the pry session.
finish Execute until current stack frame returns.
next Execute the next line within the current stack frame.
step Step execution into the next line or method.
help hist
[12] pry(main)> help hist
Usage: hist [--head|--tail]
hist --all
hist --head N
hist --tail N
hist --show START..END
hist --grep PATTERN
hist --clear
hist --replay START..END
hist --save [START..END] FILE
Aliases: history
Show and replay Readline history.
-a, --all Display all history
-H, --head Display the first N items
-T, --tail Display the last N items
-s, --show Show the given range of lines
-G, --grep Show lines matching the given pattern
-c, --clear Clear the current session's history
-r, --replay Replay a line or range of lines
--save Save history to a file
-e, --exclude-pry Exclude Pry commands from the history
-n, --no-numbers Omit line numbers
-h, --help Show this message.
親記事
外部資料