Modular Programming

Months

Goal: create a package to display the months of the year.

Steps:

  1. Convert the Months procedure below to a package.

  2. Create the specification and body of the Months package.

Requirements:

  1. Months must contain the declaration of strings for each month of the year, which are stored in three-character constants based on the month's name.

    • For example, the string "January" is stored in the constant Jan. These strings are then used by the Display_Months procedure, which is also part of the Months package.

Remarks:

  1. The goal of this exercise is to create the Months package.

    1. In the code below, Months is declared as a procedure.

      • Therefore, we need to convert it into a real package.

    2. You have to modify the procedure declaration and implementation in the code below, so that it becomes a package specification and a package body.

-- Create specification for Months package, which includes -- the declaration of the Display_Months procedure. -- procedure Months;
-- Create body of Months package, which includes -- the implementation of the Display_Months procedure. -- procedure Months is procedure Display_Months is begin Put_Line ("Months:"); Put_Line ("- " & Jan); Put_Line ("- " & Feb); Put_Line ("- " & Mar); Put_Line ("- " & Apr); Put_Line ("- " & May); Put_Line ("- " & Jun); Put_Line ("- " & Jul); Put_Line ("- " & Aug); Put_Line ("- " & Sep); Put_Line ("- " & Oct); Put_Line ("- " & Nov); Put_Line ("- " & Dec); end Display_Months; begin null; end Months;
with Ada.Command_Line; use Ada.Command_Line; with Ada.Text_IO; use Ada.Text_IO; with Months; use Months; procedure Main is type Test_Case_Index is (Months_Chk); procedure Check (TC : Test_Case_Index) is begin case TC is when Months_Chk => Display_Months; end case; end Check; begin if Argument_Count < 1 then Put_Line ("ERROR: missing arguments! Exiting..."); return; elsif Argument_Count > 1 then Put_Line ("Ignoring additional arguments..."); end if; Check (Test_Case_Index'Value (Argument (1))); end Main;

Operations

Goal: create a package to perform basic mathematical operations.

Steps:

  1. Implement the Operations package.

    1. Declare and implement the Add function.

    2. Declare and implement the Subtract function.

    3. Declare and implement the Multiply: function.

    4. Declare and implement the Divide function.

  2. Implement the Operations.Test package

    1. Declare and implement the Display procedure.

Requirements:

  1. Package Operations contains functions for each of the four basic mathematical operations for parameters of Integer type:

    1. Function Add performs the addition of A and B and returns the result;

    2. Function Subtract performs the subtraction of A and B and returns the result;

    3. Function Multiply performs the multiplication of A and B and returns the result;

    4. Function Divide: performs the division of A and B and returns the result.

  2. Package Operations.Test contains the test environment:

    1. Procedure Display must use of the functions from the parent (Operations) package as indicated by the template in the code below.

package Operations is -- Create specification for Operations package, including the -- declaration of the functions mentioned above. -- end Operations;
package body Operations is -- Create body of Operations package. -- end Operations;
package Operations.Test is -- Create specification for Operations package, including the -- declaration of the Display procedure: -- -- procedure Display (A, B : Integer); -- end Operations.Test;
package body Operations.Test is -- Implement body of Operations.Test package. -- procedure Display (A, B : Integer) is A_Str : constant String := Integer'Image (A); B_Str : constant String := Integer'Image (B); begin Put_Line ("Operations:"); Put_Line (A_Str & " + " & B_Str & " = " & Integer'Image (Add (A, B)) & ","); -- Use the line above as a template and add the rest of the -- implementation for Subtract, Multiply and Divide. end Display; end Operations.Test;
with Ada.Command_Line; use Ada.Command_Line; with Ada.Text_IO; use Ada.Text_IO; with Operations; with Operations.Test; use Operations.Test; procedure Main is type Test_Case_Index is (Operations_Chk, Operations_Display_Chk); procedure Check (TC : Test_Case_Index) is begin case TC is when Operations_Chk => Put_Line ("Add (100, 2) = " & Integer'Image (Operations.Add (100, 2))); Put_Line ("Subtract (100, 2) = " & Integer'Image (Operations.Subtract (100, 2))); Put_Line ("Multiply (100, 2) = " & Integer'Image (Operations.Multiply (100, 2))); Put_Line ("Divide (100, 2) = " & Integer'Image (Operations.Divide (100, 2))); when Operations_Display_Chk => Display (10, 5); Display ( 1, 2); end case; end Check; begin if Argument_Count < 1 then Put_Line ("ERROR: missing arguments! Exiting..."); return; elsif Argument_Count > 1 then Put_Line ("Ignoring additional arguments..."); end if; Check (Test_Case_Index'Value (Argument (1))); end Main;