README.md in mathn-0.1.0 vs README.md in mathn-0.2.0
- old
+ new
@@ -1,11 +1,50 @@
# Mathn
-Welcome to your new gem! In this directory, you'll find the files you need to be able to package up your Ruby library into a gem. Put your Ruby code in the file `lib/mathn`. To experiment with that code, run `bin/console` for an interactive prompt.
+[](https://travis-ci.org/ruby/mathn)
-TODO: Delete this and the text above, and describe your gem
+mathn serves to make mathematical operations more precise in Ruby and to integrate other mathematical standard libraries.
+Without mathn:
+
+```ruby
+3 / 2 => 1 # Integer
+```
+
+With mathn:
+
+```ruby
+3 / 2 => 3/2 # Rational
+```
+
+mathn keeps value in exact terms.
+
+Without mathn:
+
+```ruby
+20 / 9 * 3 * 14 / 7 * 3 / 2 # => 18
+```
+
+With mathn:
+
+```ruby
+20 / 9 * 3 * 14 / 7 * 3 / 2 # => 20
+```
+
+## Global Behavioral changes
+
+While older version of 'mathn', just by required, caused changes to
+the behavior (and even the types) of operations on classes like
+Integer newer `mathn` introduces the refinements `Math::N`, and you
+have to enable it.
+
+Before ruby 2.5, `mathn` was part of the ruby standard library. It was
+was [deprecated in ruby 2.2.0](https://github.com/ruby/ruby/blob/v2_2_0/NEWS#stdlib-compatibility-issues-excluding-feature-bug-fixes),
+and [removed from ruby 2.5.0](https://github.com/ruby/ruby/blob/ruby_2_5/NEWS#stdlib-compatibility-issues-excluding-feature-bug-fixes).
+In order to use the library with a current version of ruby,
+you must install it as a gem.
+
## Installation
Add this line to your application's Gemfile:
```ruby
@@ -20,22 +59,24 @@
$ gem install mathn
## Usage
-TODO: Write usage instructions here
+```ruby
+require 'mathn'
+using Math::N
+```
## Development
After checking out the repo, run `bin/setup` to install dependencies. Then, run `rake test` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run `bundle exec rake install`. To release a new version, update the version number in `version.rb`, and then run `bundle exec rake release`, which will create a git tag for the version, push git commits and tags, and push the `.gem` file to [rubygems.org](https://rubygems.org).
## Contributing
-Bug reports and pull requests are welcome on GitHub at https://github.com/hsbt/mathn.
+Bug reports and pull requests are welcome on GitHub at https://github.com/ruby/mathn.
## License
The gem is available as open source under the terms of the [MIT License](http://opensource.org/licenses/MIT).
-