Ada

Ada is a high-level structured programming language designed with a focus on safety due to its roots in embedded and real-time systems. From Wikipedia:

[Ada] has built-in language support for design by contract (DbC), extremely strong typing, explicit concurrency, tasks, synchronous message passing, protected objects, and non-determinism. Ada improves code safety and maintainability by using the compiler to find errors in favor of runtime errors. Ada is an international technical standard, jointly defined by the International Organization for Standardization (ISO), and the International Electrotechnical Commission (IEC). As of 2020, the standard, called Ada 2012 informally,[13] is ISO/IEC 8652:2012.[14]

This container includes the GCC GNAT implementation of Ada.

Hello World

#!/usr/bin/env sh

cd /hello-world
gnatmake -q fraglet.adb
./fraglet "$@"

Coding Guide

Language Version

Ada (GNAT compiler, Alpine Linux)

Execution Model

• Compiled language using GNAT (GNU Ada Translator)
• Code is compiled to a binary using gnatmake, then executed
• Standard Ada execution model with a main procedure

Key Characteristics

• Statically typed
• Case-insensitive keywords (but case-sensitive identifiers)
• Strong typing with type safety
• Requires explicit compilation step
• Uses GNAT compiler (GCC-based Ada compiler)

Fragment Authoring

Write a complete Ada program. Your fragment must define procedure Fraglet as the main entry point. Include any with imports you need.

Available Packages

Standard Ada library packages are available:

• Ada.Text_IO - Text I/O (Put_Line, Get_Line, End_Of_File, etc.)
• Ada.Characters.Handling - Character/string case (e.g. To_Upper)
• Ada.Command_Line - Command-line arguments (Argument_Count, Argument (I))
• Ada.Integer_Text_IO, Ada.Strings, Ada.Numerics, etc.

Common Patterns

• Output: Put_Line ("message");
• Variables: X : Integer := 10;
• Procedures: procedure Name is begin ... end Name;
• Functions: function Add (A, B : Integer) return Integer is begin return A + B; end Add;
• Arrays: Arr : array (1..10) of Integer;
• Loops: for I in 1..10 loop ... end loop;
• Conditionals: if X > 0 then ... end if;
• Stdin: Get_Line (Line, Last) in a while not End_Of_File loop; use Ada.Characters.Handling.To_Upper for uppercase.
• Command-line args: Ada.Command_Line.Argument_Count, Ada.Command_Line.Argument (I) (I from 1 to Argument_Count).

Examples

-- Simple output
with Ada.Text_IO; use Ada.Text_IO;
procedure Fraglet is
begin
  Put_Line ("Hello from fragment!");
end Fraglet;

-- With local variables
with Ada.Text_IO; use Ada.Text_IO;
procedure Fraglet is
  A : Integer := 5;
  B : Integer := 10;
begin
  Put_Line ("Sum: " & Integer'Image (A + B));
end Fraglet;

-- Reading stdin
with Ada.Text_IO; use Ada.Text_IO;
with Ada.Characters.Handling;
procedure Fraglet is
  Line : String (1 .. 1024);
  Last : Natural;
begin
  while not End_Of_File loop
    Get_Line (Line, Last);
    Put_Line (Ada.Characters.Handling.To_Upper (Line (1 .. Last)));
  end loop;
end Fraglet;

-- Command-line args
with Ada.Text_IO; use Ada.Text_IO;
with Ada.Command_Line;
procedure Fraglet is
begin
  for I in 1 .. Ada.Command_Line.Argument_Count loop
    Put_Line (Ada.Command_Line.Argument (I));
  end loop;
end Fraglet;

Caveats

• Fragments must be valid Ada code that compiles
• Remember Ada uses & for string concatenation
• Use Integer'Image or Float'Image to convert numbers to strings
• Variables must be declared before use
• The code is compiled fresh each time, so compilation errors will fail execution
• Ada is case-insensitive for keywords but case-sensitive for identifiers
• Statement terminators (;) are required

Fraglet Scripts

Echo Args

#!/usr/bin/env -S fragletc --vein=ada
with Ada.Text_IO; use Ada.Text_IO;
with Ada.Command_Line;

procedure Fraglet is
begin
  Put ("Args:");
  for I in 1 .. Ada.Command_Line.Argument_Count loop
    Put (" " & Ada.Command_Line.Argument (I));
  end loop;
  New_Line;
end Fraglet;

Stdin Upper

#!/usr/bin/env -S fragletc --vein=ada
with Ada.Text_IO; use Ada.Text_IO;
with Ada.Characters.Handling;

procedure Fraglet is
  Line : String (1 .. 1024);
  Last : Natural;
begin
  while not End_Of_File loop
    Get_Line (Line, Last);
    Put_Line (Ada.Characters.Handling.To_Upper (Line (1 .. Last)));
  end loop;
end Fraglet;

Test

#!/usr/bin/env -S fragletc --vein=ada
with Ada.Text_IO; use Ada.Text_IO;

procedure Fraglet is
begin
  Put_Line ("Hello World!");
end Fraglet;

Connections

Container Info