Muldis Data Engine Reference: .NET (MDE) - Reference interpreter implementation of Muldis Data Language
The fully-qualified name of what this document describes is
Muldis_Data_Engine_Reference_DotNet https://muldis.com 0.1.
IMPORTANT NOTICE: The current project "Muldis Data Engine Reference" has been mostly superseded by the other project "Muldis Data Library"; the latter is a rewrite of a majority of the former. Any further work on the current project is blocked until "Muldis Data Library" has been sufficiently completed, after which the latter is intended to be a foundation for the current project.
MDE is a work in progress. It is not yet ready to use for its intended purpose, nor is it yet even a minimum viable product. This documentation will be rewritten or updated as the project develops.
MDE is fundamentally a library that provides an embedded virtual machine implementation of the Muldis Data Language which is also an embedded database engine and an embedded type system for the host language.
The standard formats for moving data and code between the virtual machine and its host are Muldis Object Notation (MUON), either the string-based Plain Text Format or the .NET data structure based format.
A utility application is also provided that reads in a Muldis Data Language "main program" in the form of a MUON text file and passes it to the virtual machine to compile and execute, essentially being a runtime of a form that is typical of scripting languages. The program to run is specified with a command-line argument.
MDE is expressly designed to have no dependencies besides a modern version of the core C# language and .NET standard library, and be a low-overhead leaf dependency for other projects. Since modern .NET is cross-platform, MDE should work on any operating system that it supports.
A rudimentary version of the MDE virtual machine library is implemented now, and one can import and export data and execute some Muldis Data Language routines on that data. Import/export only works currently in terms of an outdated form of the Muldis Object Notation .NET hosted format, and the MUON Plain Text format is not yet implemented for importing.
A utility application is also implemented which performs some rudimentary testing on the virtual machine, trying to use its API, importing some data, and trying to invoke a Muldis Data Language routine or two.
That utility application prints out to the command-line quasi-MUON-Plain-Text serializations of the imported data, so that it actually looks like it is doing something.
The utility application also reads in a MUON source file as if it was going to run it, but since parsing these is not yet implemented, that part no-ops.
In order to run the MDE utility application, you first have to compile it, which can be done in the usual manner using Microsoft's Visual Studio, which can be obtained here (with no-cost Community licensing an option):
https://visualstudio.microsoft.com
MDE is implemented with .NET 8 (2023) which is cross-platform so you can use either the Apple MacOS or Microsoft Windows version of Visual Studio. I have done all development and testing so far on MacOS however.
Microsoft also provides command-line alternative compilers and runtimes specific to modern .NET versions, instead of needing a full Visual Studio:
You would want to have a modern Microsoft dotnet tool
version on your system if you want to build it on the command line:
dotnet clean ; dotnet build
Once the MDE .NET project has been compiled to a native executable, you can run it on the command line, such as MacOS Terminal or Windows Console.
A thin wrapper UNIX shell script has been provided that can be used once the project is compiled.
Here is an example of its use:
sh muldisder.sh perform --in=corpora/Syntax_Plain_Text/spec_all_examples.muon
Simply running it without arguments or with help will display a Usage message.
sh muldisder.sh help
I have not yet produced an alternate thin wrapper Windows shell script, but that is intended to be done soon.
Darren Duncan - darren@DarrenDuncan.net
Muldis Data Engine Reference: .NET (MDE) is Copyright © 2015-2024, Muldis Data Systems, Inc.
MDE is free software; you can redistribute it and/or modify it under the terms of the Apache License, Version 2.0 (AL2) as published by the Apache Software Foundation (https://www.apache.org). You should have received a copy of the AL2 as part of the MDE distribution, in the file LICENSE/Apache-2.0.txt; if not, see https://www.apache.org/licenses/LICENSE-2.0.
Any versions of MDE that you modify and distribute must carry prominent notices stating that you changed the files and the date of any changes, in addition to preserving this original copyright notice and other credits. MDE is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
While it is by no means required, the copyright holder of MDE would appreciate being informed any time you create a modified version of MDE that you are willing to distribute, because that is a practical way of suggesting improvements to the standard version.