This project is the result of a lab assignment for the Software Construction course at the UvA. The goal of the assignment is to build a DSL for questionnaires, called QL. The lab assignment is based on the Language Workbench Challenge 2013 LWC'13. A questionnaire consists of a sequence of questions and derived values presented to a user by rendering it as a GUI. Later questions may only be visible depending on answers given to earlier questions.

• Questions are enabled and disabled when different values are entered.
• The type checker detects:
  • Reference to undefined questions
  • Duplicate question declarations with different types
  • Conditions that are not of the type boolean
  • Operands of invalid type to operators
  • Cyclic dependencies between questions
  • Duplicate labels (warning)
• The language supports booleans, integers and string values.
• Different data types in QL map to different (default) GUI widgets.

Here's a simple questionnaire in QL from the domain of tax filing:

form taxOfficeExample {
  "Did you sell a house in 2010?"
    hasSoldHouse: boolean
  "Did you buy a house in 2010?"
    hasBoughtHouse: boolean
  "Did you enter a loan?"
    hasMaintLoan: boolean

  if (hasSoldHouse) {
    "What was the selling price?"
      sellingPrice: money
    "Private debts for the sold house:"
      privateDebt: money
    "Value residue:"
      valueResidue: money =
        (sellingPrice - privateDebt)
  }
}

Place the questionnaire in resources and run the main class nl.uva.ql.main.Main using this questionnaire.