Many extension packages already exist to make AutoLisp into a more full-blooded extension language for AutoCAD. The following are some which have potential:
OpenDCL
This project is a set of ARX libraries to be loaded into AutoCAD. Its main aim is to provide an updated GUI for AutoLisp files. Though some of its functions do more than just provide GUI features.
It's an open source project and can be found in the Source Forge repository:
ObjectDCL
Similar to OpenDCL in concept, this can be seen as the commercial version as it's not open source. There are several similarities, though implementation is different. Investigation into the pros and cons between the two needs further attention.
DosLib
DosLib is an extension by Robert McNeel & Associates which adds some functions to AutoLisp to work with the underlying operating system. It has more features than simply allowing file / folder access, though its main intention is to make file management easier. There are some overlaps between this and OpenDCL.
ADOLisp
AADOLisp incorporates ActiveX to ADO libraries in order to connect to data sources - such as databases and spreadsheets. It's written entirely in AutoLisp itself, though making extensive use of VisualLisp functions to work with the ActiveX connection through ADO.
DynamicWrapperX
DynamicWrapperX is a small DLL which can be loaded as a standard ActiveX library through VisualLisp. This opens some functions to load/run DotNet assemblies into AutoLisp. There are some caveats as it only uses 32bit addressing, thus 64bit systems may have strange results, especially if working with things like pointers.
