Consider rewritting bussiness logic in Ada

[hurufu]

Ada is a strongly typed language that is well suited for describing Nexo specification.

Pros:

1. Very-strong type checking
2. Well defined bit fields that are used a lot in EMV and Nexo.
3. Preconditions and postconditions that actually are there in the nexo specification, and it would be nice to have them. They usually state which variables must change their value or must only be read.
4. Maps well from Drakon
   1. it has goto which is needed for blazing fast implementation
   2. high-level looping constructs compared to C
   3. nested function which may be used to implement procedures/functions with multiple entry points

Cons:

1. I have to implement Ada generator from Drakon diagram
2. I have to learn Ada well enough to be able to design this generator properly
3. There aren't many free and open source ASN.1 compilers for Ada.

References:

• Data Modelling with ASN.1 for Space Applications
• asn1scc compiler
• Ada courses

[hurufu]

Additionally this request is similar to #36, but arguably is harder to implement. As a side note, I had an idea long time ago to write the diagrams in specifically crafted language (like haxe) that should be easily convertible to other languages (like C, C++, Java, Ada, Zig, or JavaScript).

[hurufu]

Licensing is also a topic that is needed to be considered. It looks like Ada code compiled by gnat compiler from FSF (gcc-ada package) adds an explicit GPLv3 exception that permits to use their runtime library in proprietary software. It is located at /usr/share/licenses/gcc-ada/RUNTIME.LIBRARY.EXCEPTION for default Arch Linux installaion. And is available online at https://www.gnu.org/licenses/gcc-exception-3.1.html.

[hurufu]

Link to comp.lang.ada conversation.