Description

This ripl plugin allows you to evaluate multiple lines of Ruby code.

Install

Install the gem with

gem install ripl-multi_line

Usage

Add the following line to your ~/.riplrc

require 'ripl/multi_line'

Hint: In multi-line situations, you can press ctrl+c and the last line will be removed.

Options

You can customize your multi-line prompt with the :multi_line_prompt option. For example, put this into your ~/.riplrc:

Ripl.config[:multi_line_prompt] = ' > '

It also takes a proc as value.

Then there is the :multi_line_history option. The default value is :compact which tries to squeeze your last multi-line block into one line (works best in mri, in about 98% of all cases).

>> def some_multi_line_block
|    42
|  end #=> nil
# Press <UP>
>> def some_multi_line_block; 42; end

Another value is :block, which joins the multi-line block with new-lines.

To leave the history untouched, set it to :plain or a false value.

AutoIndent

Check out the ripl-auto_indent plugin to get ruby syntax indention.

MultiLine detection

To use your own multi-line detection engine, implement your version at lib/ripl/multi_line/your_correct_detection.rb in which you overwrite Shell#multiline? in a Ripl::MultiLine sub-module named YourCorrectDetection and set Ripl.config[:multi_line_engine] to :your_correct_detection. See lib/ripl/multi_line/*.rb for examples.

Currently available engines:

  • :live_error (default) - Simply evaluate expression, if it throws a multi-line syntax error, fall back to multi-line input mode. Sounds scary, but works pretty well in practice.

  • :error_check - Same principle as :live_error, but don’t do it live

  • :ripper - Analyze input with Ripper (comes with 1.9, but there is also a 1.8 gem).

  • :ruby_parser - Use ruby_parser gem (1.8 only)

  • :irb - You left irb, but you are still used to its multi-line behaviour? Use irb’s RubyLex!

None of the above solutions is perfect, so… maybe it’s time to roll your own ;)

Troubleshooting

Problem: “I’ve required ripl-multi_line, but it doesn’t work”

Answer: This is probably caused by a plugin, which overwrites :before_loop, but does not call super (or you are using ripl-profiles older than 0.2.0). You can manually work around this issue with this snippet (but you should fix the general problem):

require 'ripl/multi_line/live_error.rb'
Ripl::MultiLine.engine = Ripl::MultiLine::LiveError
Ripl::Shell.include Ripl::MultiLine.engine

TODO

  • Write thousands of test cases

J-_-L

Contributions & influences by cldwalker and godfat.