A translator for Ada 83 to Diana with tools for using Diana

Diana is a translator for Ada 83 to Diana, accompanied by tools for working with Diana. It was originally developed by William Easton of Peregrine Systems, Inc. This repository contains a copy of the original software and a modified version for easier integration with the Alire package manager.

• origin branch: Contains the original release of the software, preserved in its unmodified form.
• main branch: Contains modifications to the original release to enable easier usage with Alire.

This software system is an Ada front end, that is a system which translates Ada into Diana, together with associated tools for use of the Diana.

The front end is to be considered a prototype version. It presently converts statically correct Ada to the corresponding Diana representation; there is no guarantee that statically incorrect programs will be diagnosed as such. (It is the intention to replace this front end with a production-quality version which will also diagnose statically incorrect programs.)

The language accepted is the entire Ada language, including library support, generics, etc., but not (yet) including any of the Chapter 13 optional features. The requirement is that the front end accept the ACVC class A and class C tests.

The implementation of Diana uses a software virtual memory, implemented as a DIRECT_IO file with fixed-size pages. Diana nodes are represented as pointers into this file; the current implementation of a pointer is a record containing a node type, a page number and a location within a page. (Of course, it is strongly recommended that the details of the current implementation not be relied upon.) The definition of the Diana is given in IDL form and matches the Intermetrics 1986 draft definition of Diana (rather than that published in 1983). Program access to Diana nodes and attributes is given by an Ada packages (actually, three packages) very similar to that given in the 1983 Diana specification.

The system includes utilities for processing the IDL specification of Diana to produce programs and packages required for using Diana. It also includes a LALR grammar generator (similar in scope to yacc, but implemented in Ada and tailored to the present project). In addition, a tool for printing the Diana in an indented format is included.

The system consists of about 35,000 lines of Ada source, probably about 15,000 Ada statements. Because of the virtual-memory implementation, there should be no arbitrary small limitations due to main memory table sizes.

The original release included the following prologue:

This prologue must be included in all copies of this software.
Restrictions on use or distribution:  NONE

Based on this statement, we have added the Unlicense license file, which closely aligns with the lack of restrictions on usage or distribution expressed in the original prologue.

This software and its documentation are provided "AS IS" and without any expressed or implied warranties whatsoever. No warranties as to performance, merchantability, or fitness for a particular purpose exist.

The user is advised to test the software thoroughly before relying on it. The user must assume the entire risk and liability of using this software. In no event shall any person or organization of people be held responsible for any direct, indirect, consequential or inconsequential damages or lost profits.

1. To use the modified version with Alire, clone the repository and switch to the main branch.
2. For historical reference or to work with the original version, switch to the origin branch.

Contributions are welcome to further improve compatibility, documentation, and tools for using Diana. Please submit pull requests or issues if you encounter problems or have suggestions.