StrategyBag
Ruby DSL for making conditionals more readable by defining a set of strategies. Each strategy has a set of conditions and an action. The runner will select a strategy that meets the conditions and executes it.
Installation
Add this line to your application's Gemfile:
gem 'strategy_bag'
And then execute:
$ bundle
Or install it yourself as:
$ gem install strategy_bag
Example
Before:
module Calc
extend self
def calc(a, b, c)
if a > 10
if b > 10
if c > 10
a + b - 2 * c
else
a + b + c
end
else
if c > 20
a + b - c
else
a + b + c
end
end
else
if b + c > 10
b + c - a
end
end
end
endAfter:
require 'strategy_bag'
module StrategicCalc
extend self
def calc(a, b, c)
Solver.new(a, b, c).run
end
class Solver < StrategyBag
params :a, :b, :c
condition(:a_high?, :a_low?) { a > 10 }
condition(:b_high?, :b_low?) { b > 10 }
condition(:c_high?, :c_low?) { c > 10 }
condition(:c_max?, :c_not_max?) { c > 20 }
condition(:bc_high?, :bc_low?) { b + c > 10 }
strategy do
condition :a_high?
condition :b_high?
condition :c_high?
action do
a + b - 2 * c
end
end
strategy do
condition :a_high?
condition :b_high?
condition :c_low?
action do
a + b + c
end
end
strategy do
condition :a_high?
condition :b_low?
condition :c_max?
action do
a + b - c
end
end
strategy do
condition :a_high?
condition :b_low?
condition :c_not_max?
action do
a + b + c
end
end
strategy do
condition :a_low?
condition :bc_high?
action do
b + c - a
end
end
default do
nil
end
end
endContributing
- Fork it ( http://github.com/bagilevi/strategy_bag/fork )
- Create your feature branch (
git checkout -b my-new-feature) - Commit your changes (
git commit -am 'Add some feature') - Push to the branch (
git push origin my-new-feature) - Create new Pull Request