quester

Aim

Create a software that automatically solves a question with dynamic values with a piece of code.

Example

Consider the following questions and their answers:

• Is it possible to add the following units: 1 kilometer and 1 mile? Yes.
• Is it possible to add the following units: 1 kilometer and 1 kilogram? No.

The solution to these questions is fairly simple. If the dimensions of the units are the same, they can be added. Else, they cannot be added.

If we had to write the solution as a solver code, it would simply be:

unit_1.dimension == unit_2.dimension ? ‘Yes’ : ‘No’

Input YAML

The input to the system is given as a yaml file.

text: >
  Is it possible to add the following units: 1 kilometer and 1 mile?
variables:
  - unit_1
  - unit_2
  - "yes_or_no : String"
test_cases:
  - 
    -
      name: unit_1
      value: Kilometer
    -
      name: unit_2
      value: Mile
    -
      name: yes_or_no
      value: "\"yes\""

  - 
    -
      name: unit_1
      value: Kilometer
    -
      name: unit_2
      value: Kilogram
    -
      name: yes_or_no
      value: "\"no\""

solvers:
  - 
    id: 1
    variable: yes_or_no
    condition: eq
    code: >
      #
          unit_1.dimension == unit_2.dimension ? ‘Yes’ : ‘No’
source: >
  This question was created by Fazil Basheer for demo purpose.

Output Crystal Code

By running crystal quester/generator.cr, the application will generate the following files based on the above YAML.

Scenario File

require "../../ilm/**"

class Scenario
  property unit_1 : Unit
  property unit_2 : Unit
  property yes_or_no : String
  
  def initialize(
    @unit_1,
    @unit_2,
    @yes_or_no,
    
  );end

  def test
    it "should pass" do
      solver = Solver.new(
        unit_1: unit_1,
        unit_2: unit_2,
        
      )

      answer = solver.solve

      answer.should eq(yes_or_no)
    end
  end
end

Solver File

class Solver
  property unit_1 : Unit
  property unit_2 : Unit
  
  def initialize(
    @unit_1,
    @unit_2,
        
  );end

  def solve
    #
    unit_1.dimension == unit_2.dimension ? ‘Yes’ : ‘No’

  end
end

Spec File

require "spec"

require "./scenario.cr"
require "./solver.cr"

describe Solver do
  settings = [

    {
      unit_1: Unit::KILOMETER,
      unit_2: Unit::MILE,
      yes_or_no: "yes",
      
    },
    
    {
      unit_1: Unit::KILOMETER,
      unit_2: Unit::KILOGRAM,
      yes_or_no: "no",
      
    },
    
  ]

  settings.each do |setting|
    Scenario.new(
      unit_1: setting[:unit_1],
      unit_2: setting[:unit_2],
      yes_or_no: setting[:yes_or_no],
      
    ).test
  end
end

Ilm

Ilm is a crystal library that encapsulates the concepts of science. To make the above question work, we must add the unit 'Mile' to Ilm.

inside the class definition of Unit at ilm/unit.cr, add the following snipped in the appropriate location.

class Unit
  ...
  MILE = new(symbol: 'm', dimension: Dimension::L)
  ...
end

Spec

By running crystal spec/questions/:id, the crystal code that was generated will be executed and the tests will pass if everything is fine.