Version: 4.1.0
Date: 2025-12-18
SPDX-License-Identifier: BSD-3-Clause
License File: See the LICENSE file in the project root
Copyright: © 2025 Michael Gardner, A Bit of Help, Inc.
Status: Released

The Functional library is 100% embedded-safe with ZERO heap allocations. All types (Result<T,E>, Option<T>, Either<L,R>) use stack-based discriminated records.

The library source code does NOT contain pragma Restrictions to allow testing with AUnit (which uses recursion). Instead, your application should apply the restrictions.

cp functional/config/embedded_restrictions.adc ./gnat.adc
alr build  # Restrictions applied automatically

project My_App is
   package Compiler is
      for Local_Configuration_Pragmas use
        "../functional/config/embedded_restrictions.adc";
   end Compiler;
end My_App;

alr exec -- gprbuild -gnatec=functional/config/embedded_restrictions.adc

The embedded_restrictions.adc file applies:

Heap Safety:

• No_Allocators - No explicit "new"
• No_Implicit_Heap_Allocations - No hidden heap use
• No_Anonymous_Allocators - No anonymous access with new
• No_Coextensions - No discriminant allocations
• No_Local_Allocators - No local pool allocations

Additional Safety:

• No_Finalization - No controlled types
• No_Nested_Finalization - No nested controlled types
• No_Recursion - Stack safety (no unbounded growth)

The library is designed to comply with these restrictions. To verify:

alr exec -- gprbuild -P functional.gpr \
  -gnatec=config/embedded_restrictions.adc

If this builds successfully, the library complies.

This is standard Ada library practice:

• Library: Compatible with restrictions (source unrestricted)
• Tests: Can use AUnit (needs recursion)
• Applications: Choose their own restriction policy
• Verification: Release process checks compliance

See docs/EMBEDDED_RESTRICTIONS_SOLUTION.md (in zoneinfo project) for detailed explanation.