Hello,
I am learning ADA language at my university and need help with the following question.

1. Write the iterative version and recursive version of a program that determines whether a given word is a palindrome. For instance, eve is a palindrome

2. write a program that reads a given word by the user and prints whether it is a palindrome on the screen.

Your help is very much appreciated! Thank you

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The issue of getting the equivalent command of the Unix command cat on Windows has been discussed for example here: What is the Windows equivalent of the Unix command cat?

I have looked at the project MinGW here: MinGW - Minimalist GNU for Windows Files

I have installed the file mingw-get-setup.exe and now I have a gui with which I can retrieve necessary Unix tools by downloading from the internet. But I do not know which of these tools has/have the cat command.

I would like to use the cat command to merge Ada specifications and bodies files so as to distribute the codes as just one .ada file on which other users can use the gnatchop command to retrieve the original files again.

If there are other better projects on Windows to obtain the cat command directly in a single Windows installation unlike the MinGW project in which tools have to be installed by downloading from the internet, I am interested.

Background

This exercise was prompted by the need for Scripted Testing to be supported by – as far as possible – code generation. The need is for the public or interfacing view of a supporting part (domain) of a system to be able to log calls made to it and to provide values on calls to it, using a scripting mechanism.

I'm new to Ada and not sure how to fix this code. It appears it is about format issue, but don't know what is causing this. I am trying to read two files called a.txt and b.txt then compute the inverse of it. Sorry again am just stuck.

Here is the input files

A.txt

2 -2 4 -2 2 0 
1 0 4 -3 0 0
1 1 1 1 1 1 
1 0 0 -1 0 0
3 0 0 -3 0 2
1 0 0 0 -2 4

B.txt

13
18
51
82
32
12

here is my code

with Ada.Text_IO, Ada.Float_Text_IO, Ada.Integer_Text_IO;
use Ada.Text_IO, Ada.Float_Text_IO, Ada.Integer_Text_IO;

procedure Matrix_Inverse is

   type Matrix is array (1 .. 6, 1 .. 6) of Float;
   type Vector is array (1 .. 6) of Float;
   
   function Get_Matrix_From_File(Filename : String) return Matrix is
      A : Matrix := (others => (others => 0.0));
      File : File_Type;
      Line : String (1 .. 20);
      Last : Natural;
   begin
      Open (File, In_File, Filename);
      for I in A'Range(1) loop
         Get_Line (File, Line, Last);
         for J in A'Range(2) loop
            A (I, J) := Float'Value (Line (1 .. Last));
            Get (File, Line);
            Get_Line (File, Line, Last);
         end loop;
         A (I, 6) := Float'Value (Line (1 .. Last));
      end loop;
      Close (File);
      return A;
   end Get_Matrix_From_File;
   
   function Get_Vector_From_File(Filename : String) return Vector is
      B : Vector := (others => 0.0);
      File : File_Type;
   begin
      Open (File, In_File, Filename);
      for I in B'Range loop
         Get (File, B (I));
      end loop;
      Close (File);
      return B;
   end Get_Vector_From_File;
   
   procedure Print_Matrix(A : Matrix) is
   begin
      for I in A'Range(1) loop
         for J in A'Range(2) loop
            Put (A (I, J), 6, 2);
            Put (" ");
         end loop;
         New_Line;
      end loop;
   end Print_Matrix;
   
   function Inverse(A : Matrix) return Matrix is
      Inv : Matrix := (others => (others => 0.0));
      Identity : Matrix := (others => (others => 0.0));
   begin
      for I in Identity'Range(1) loop
         Identity (I, I) := 1.0;
      end loop;
      
      for I in A'Range(1) loop
         if A (I, I) = 0.0 then
            for J in I + 1 .. A'Range(1)'Last loop
               if A (J, I) /= 0.0 then
                  for K in A'Range(2) loop
                     A (I, K) := A (I, K) + A (J, K);
                     Identity (I, K) := Identity (I, K) + Identity (J, K);
                  end loop;
                  exit;
               end if;
            end loop;
         end if;
    for J in A'Range(1) loop
      if J /= I then
          declare
            Factor : constant Float := A (J, I) / A (I, I);
          begin
            for K in A'Range(2) loop
                A (J, K) := A (J, K) - Factor * A (I, K);
                Identity (J, K) := Identity (J, K) - Factor * Identity (I, K);
            end loop;
          end;
      end if;
    end loop;

    for I in A'Range(1) loop
      declare
          Diagonal : constant Float := A (I, I);
      begin
          for J in A'Range(2) loop
            Identity (I, J) := Identity (I, J) / Diagonal;
          end loop;
      end;
    end loop;

      return Identity;
    end Inverse;

  function Solve(A : Matrix; B : Vector) return Vector is
    Inv_A : Matrix := Inverse(A);
    Result : Vector := (others => 0.0);
  begin
    for I in Result'Range loop
        for J in Result'Range loop
          Result (I) := Result (I) + Inv_A (I, J) * B (J);
        end loop;
    end loop;
    return Result;
  end Solve;

  A : Matrix := Get_Matrix_From_File("a.txt");
  B : Vector := Get_Vector_From_File("b.txt");

  Solution : Vector := Solve(A, B);

  begin
    Put_Line("Solution:");
    for I in Solution'Range loop
        Put(Solution(I), 6, 2);
        Put(" ");
    end loop;
    New_Line;
end Matrix_Inverse;

Why does not Ada support variable function/procedure argument lists? Is it hard to implement or does it somehow go against "we should keep things secure" philosophy of the language?

Varargs were over there at least as early as C and allow very handy things like printf, the likes of which can also be found in other languages like Java or C#. Another neat example is logging functions where it is usual to pass information from all kinds of data types, not only strings, in separate arguments.

And even if this is considered non-secure technique, Ada could still make it better than at least in C by e.g. throwing an exception if there is some mismatch between format string and the actually passed arguments.

I'm working on a C++ application, Module_A, that has to use a diverse module, Module_B_Ada and Module_B_CPP depending on configuration.

Module_A + Module_B_Language will be compiled in different OS. I want to avoid duplicating Module_A to have a Module_A for Ada compilation and a Module_A for C++ compilation.

For now, the only thing that came to my mind has been to separate the code that uses the Ada module and exclude it from compilation when is compiled for C++ to avoid linking errors for unresolved symbols.

Another thing I'm thinking about is to comment the "extern" statement on the Module_A and define the Ada services to a void implementation when compiling for C++.

Have yoy ever faced a similar problem? How have you solved it?

I was looking for DTLS libraries and found this recent post on the wolfSSL website.

Exciting news in wolfSSL language bindings: we are currently exploring the possibility of adding bindings for the Ada and Spark languages!

Ada is a programming language known for its explicitness, strong typing, and abundance of compile-time checks. It is widely used in safety-critical and high-integrity software. Spark, on the other hand, is a smaller subset of Ada that offers the invaluable ability to formally prove the correctness of your software.

We believe that wolfSSL bindings would be immensely valuable to the Ada and Spark communities. These bindings would provide a production-ready, robust, and well-tested TLS stack that supports the latest protocols (TLS1.3/DTLS1.3). Additionally, it would open the door to obtaining FIPS 140-3 and DOI-178C certifications for Ada and Spark applications that use TLS for their encrypted communications, or that want to use our wolfCrypt implementation for their cryptographic operations, such as encrypting data at rest.

As wolfSSL already supports post-quantum TLS 1.3 and DTLS 1.3, these bindings would also naturally allow you to make your Ada and SPARK applications quantum-safe.

Are you interested in an Ada/Spark wrapper? If so, please do not hesitate to contact us at [email protected] with any questions, comments, or suggestions.

Source: wolfSSL ADA/Spark language bindings – wolfSSL

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