The First Commercial IDE
Integrated development environments (IDEs) are commonplace in today's software development industry. 30+ years ago they had never been heard of, being largely in the domain of research. Xerox PARC created XDE to facilitate the development of large-scale programs - its goals were to reduce the cost of programming (in terms of people time and processor time) and to increase the quality of code produced (in terms of efficiency, reliability, and ease of maintenance).
XDE was designed to be used on a powerful personal workstation - personal being a key concept. In an era dominated by timesharing mainframe systems and prohibitively expensive computer hardware, it was nothing short of revolutionary. The development environment's goals were met by three key components - the Mesa language, the Pilot operating system, and the Mesa Processor hardware. The three components were designed expressly to support the goals of XDE (rather than the other way round).
XDE consisted of an integrated set of cooperating programs, or tools, that supported and simplified many common programming tasks. This toolkit was completely open-ended, however, with the developer free to create new tools as required. As the sole user of an XDE development machine, the user could modify the environment as much as s/he liked. S/he had access to all the system routines, both simple and complex, as documented in the two main programming texts - the Mesa Programmer's Manual and the Pilot Programmer's Manual.
Tajo
The XDE tools environment, Tajo, was a set of integrated tools designed for creating, debugging, and maintaining large programs. The main difference between this and other development environments of the time was that Tajo's philosophy was that the user should be in control at all times, not the system. The user should be free to interact with any of the available tools at any time. This differed radically from existing development environments based around a command-line interface. In such environments the user would have to wait until the current task was complete, eg, starting a software build would prevent the user from reading email or searching a remote machine for documentation or interface files.Tajo's user interface was based around a set of highly-interactive "windows" - rectangular partitions of a high-resolution bitmapped display, controlled by a pointing device - novel departures in a world dominated by 80x25 character terminals.
XDE Tutorials
XDE was distributed with a set of tutorials to help a new user find their way. These
files took the form of nsmail files, and were read using the standard Mail Tool.
The following tutorials come from the XDE 5.0 distribution for a 6085, and were intended to be
read in the following order:
- TeachBasics - introduction to XDE
- TeachFiles - how to work with files
- TeachText - text editing tools
- Teach6085Booting - how to boot a 6085
- TeachMailSystem - how to use the Mail Tool
- TeachPrinting - how to print files
- TeachCompile-Bind-Run - how to develop Mesa software
- TeachDebugger - debugging Mesa programs
- TeachToolBuidling - developing Tajo "tools"