Update overloading lab to not use console input

Author: frank-at-adacore

courses/ada_essentials/090_overloading/88-overloading.lab.rst

@@ -8,33 +8,36 @@ Overloading Lab
 
 * Requirements
 
-   - Create multiple functions named "Convert" to convert between digits and text representation
+   - Create multiple functions named :ada:`Convert` to convert between a character digits and its name
 
-      + One routine should take a digit and return the text version (e.g. **3** would return **three**)
+      + One routine should take a digit and return the name (e.g. **'3'** would return **three**)
 
-      + One routine should take text and return the digit (e.g. **two** would return **2**)
+      + One routine should take the name and return the digit (e.g. **two** would return **'2'**)
 
-   - Query the user to enter text or a digit and print its equivalent
-   - If the user enters consecutive entries that are equivalent, print a message
+      + Hint: enumerals for the name will be easier than dealing with strings
 
-      + e.g. **4** followed by **four** should get the message
+   - Create overloaded addition functions that will add any combination of the two (digit and name)
 
-* Hints
+      + The result can be an integer (i.e. dont worry about converting the result of :ada:`'7' + eight`)
 
-   - You can use enumerals for the text representation
+      + Hint: It might be easier to convert one to the other before adding!
 
-      + Then use *'Image* / *'Value* where needed
-
-   - Use an equivalence function to compare different types
+   - The prompt has four equations in the comments - use those to prove your code works
 
 -------------------------------------------------
 Overloading Lab Solution - Conversion Functions
 -------------------------------------------------
 
-.. container:: source_include 090_overloading/lab/overloading/answer/main.adb :start-after:--Conversion_Functions :end-before:--Conversion_Functions :code:Ada :number-lines:4
+.. container:: source_include 090_overloading/lab/overloading/answer/main.adb :start-after:conversions_begin :end-before:conversions_end :code:Ada :number-lines:5
+
+--------------------------------------
+Overloading Lab Solution - Operators
+--------------------------------------
+
+.. container:: source_include 090_overloading/lab/overloading/answer/main.adb :start-after:operators_begin :end-before:operators_end :code:Ada :number-lines:32
 
 -------------------------------------------------
 Overloading Lab Solution - Main
 -------------------------------------------------
 
-.. container:: source_include 090_overloading/lab/overloading/answer/main.adb :start-after:--Main :end-before:--Main :code:Ada :number-lines:40
+.. container:: source_include 090_overloading/lab/overloading/answer/main.adb :start-after:main_begin :end-before:main_end :code:Ada :number-lines:79

courses/ada_essentials/090_overloading/lab/overloading/ada95/main.adb

@@ -1,99 +1,153 @@
 with Ada.Text_IO; use Ada.Text_IO;
 procedure Main is
 
-   type Digit_T is range 0 .. 9;
+   --|conversions_begin
+   subtype Digit_T is Character range '0' .. '9';
    type Digit_Name_T is
      (Zero, One, Two, Three, Four, Five, Six, Seven, Eight, Nine);
 
-   function Convert (Value : Digit_Name_T) return Digit_T;
-   function Convert (Value : Character) return Digit_Name_T;
-   function Convert (Value : String) return Digit_T;
+   function Convert
+     (Value : Digit_T)
+      return Digit_Name_T;
+   function Convert
+     (Value : Digit_Name_T)
+      return Digit_T;
+   function Convert
+     (Value : Digit_Name_T)
+      return Integer;
 
-   function "=" (L : Digit_Name_T; R : Digit_T) return Boolean is
-   begin
-      return Convert (L) = R;
-   end "=";
-
-   function Convert (Value : Digit_Name_T) return Digit_T is
+   function Convert
+     (Value : Digit_T)
+      return Digit_Name_T is
    begin
       case Value is
-         when Zero  => return 0;
-         when One   => return 1;
-         when Two   => return 2;
-         when Three => return 3;
-         when Four  => return 4;
-         when Five  => return 5;
-         when Six   => return 6;
-         when Seven => return 7;
-         when Eight => return 8;
-         when Nine  => return 9;
+         when '0' =>
+            return Zero;
+         when '1' =>
+            return One;
+         when '2' =>
+            return Two;
+         when '3' =>
+            return Three;
+         when '4' =>
+            return Four;
+         when '5' =>
+            return Five;
+         when '6' =>
+            return Six;
+         when '7' =>
+            return Seven;
+         when '8' =>
+            return Eight;
+         when '9' =>
+            return Nine;
       end case;
    end Convert;
 
-   function Convert (Value : Character) return Digit_Name_T is
+   function Convert
+     (Value : Digit_Name_T)
+      return Digit_T is
    begin
       case Value is
-         when '0' => return Zero;
-         when '1' => return One;
-         when '2' => return Two;
-         when '3' => return Three;
-         when '4' => return Four;
-         when '5' => return Five;
-         when '6' => return Six;
-         when '7' => return Seven;
-         when '8' => return Eight;
-         when '9' => return Nine;
-         when others => return Zero;
+         when Zero =>
+            return '0';
+         when One =>
+            return '1';
+         when Two =>
+            return '2';
+         when Three =>
+            return '3';
+         when Four =>
+            return '4';
+         when Five =>
+            return '5';
+         when Six =>
+            return '6';
+         when Seven =>
+            return '7';
+         when Eight =>
+            return '8';
+         when Nine =>
+            return '9';
       end case;
    end Convert;
 
-   function Convert (Value : String) return Digit_T is
+   function Convert
+     (Value : Digit_Name_T)
+      return Integer is
    begin
-      return Convert (Digit_Name_T'Value (Value));
+      return Digit_Name_T'Pos (Value);
    end Convert;
+   --|conversions_end
+
+   --|operators_begin
+   function "+"
+     (Left  : Digit_T;
+      Right : Digit_Name_T)
+      return Integer;
+   function "+"
+     (Left  : Digit_Name_T;
+      Right : Digit_T)
+      return Integer;
+   function "+"
+     (Left  : Digit_T;
+      Right : Digit_T)
+      return Integer;
+   function "+"
+     (Left  : Digit_Name_T;
+      Right : Digit_Name_T)
+      return Integer;
+
+   function "+"
+     (Left  : Digit_T;
+      Right : Digit_Name_T)
+      return Integer is
+      L : constant Digit_Name_T := Convert (Left);
+   begin
+      return L + Right;
+   end "+";
+
+   function "+"
+     (Left  : Digit_Name_T;
+      Right : Digit_T)
+      return Integer is
+      Sum : constant Integer := Convert (Left) + Convert (Right);
+   begin
+      return Sum;
+   end "+";
 
-   function Get_Line return String is
-      S : String (1 .. 100);
-      L : Integer;
+   function "+"
+     (Left  : Digit_T;
+      Right : Digit_T)
+      return Integer is
+      L : constant Digit_Name_T := Convert (Left);
+      R : constant Digit_Name_T := Convert (Right);
    begin
-      Get_Line (S, L);
-      return S (1 .. L);
-   end Get_Line;
+      return L + R;
+   end "+";
 
-   Last_Entry : Digit_T := 0;
+   function "+"
+     (Left  : Digit_Name_T;
+      Right : Digit_Name_T)
+      return Integer is
+   begin
+      return Integer'(Convert (Left)) + Integer'(Convert (Right));
+   end "+";
+   --|operators_end
 
+   --|main_begin
 begin
-   loop
-      Put ("Input: ");
-      declare
-         Str : constant String := Get_Line;
-      begin
-         exit when Str'Length = 0;
-         if Str (Str'First) in '0' .. '9' then
-            declare
-               Converted : constant Digit_Name_T := Convert (Str (Str'First));
-            begin
-               Put (Digit_Name_T'Image (Converted));
-               if Converted = Last_Entry then
-                  Put_Line (" - same as previous");
-               else
-                  Last_Entry := Convert (Converted);
-                  New_Line;
-               end if;
-            end;
-         else
-            declare
-               Converted : constant Digit_T := Convert (Str);
-            begin
-               Put (Digit_T'Image (Converted));
-               if Converted = Last_Entry then
-                  Put_Line (" - same as previous");
-               else
-                  Last_Entry := Converted;
-                  New_Line;
-               end if;
-            end;
-         end if;
-      end;
-   end loop;
+
+   --  One + 2
+   Put_Line (Integer'Image (One + '2'));
+
+   --  3 + Four
+   Put_Line (Integer'Image ('3' + Four));
+
+   --  Five + Six
+   Put_Line (Integer'Image (Five + Six));
+
+   --  7 + 8
+   Put_Line (Integer'Image ('7' + '8'));
 end Main;
+--|main_end