AutoLISP

AutoLISP is a high-level, interpreted programming language dialect of Lisp used primarily for extending and customizing AutoCAD, a computer-aided design (CAD) software application developed by Autodesk. Originally introduced in 1986 with AutoCAD Release 2.1, AutoLISP allows users to automate repetitive tasks, create custom commands, and modify AutoCAD's functionality to suit specific needs and workflows.

As an embedded language within AutoCAD, AutoLISP code is typically loaded and executed within the AutoCAD environment. This integration allows access to AutoCAD's database and functions, enabling developers to manipulate drawing objects, manage layers, perform calculations, and interact with the AutoCAD user interface.

While historically significant and widely used within the AutoCAD community, AutoLISP's development has largely been superseded by newer languages like VBA (Visual Basic for Applications) and .NET. However, AutoLISP continues to be supported in current versions of AutoCAD and remains a valuable tool for many users due to its simplicity, ease of use, and extensive existing codebase. It is particularly useful for simple tasks and for maintaining legacy customizations. Its interpreted nature means that code changes can be quickly tested and implemented without the need for compilation.

AutoLISP relies on a syntax based on S-expressions (symbolic expressions), characteristic of Lisp-family languages. This syntax utilizes parentheses to define function calls and data structures. The language provides a set of built-in functions and allows users to define their own functions to perform specific tasks. Common tasks include automating drafting processes, creating custom tools, and linking AutoCAD data with external databases.