Tcl/Tk Workshop `95 - Friday: Session 8

Open Discussion on Tcl/Tk OO Extensions

John Ousterhout

• states that when the interpreter is re-worked, he will attempt to put things into the core to make OO extensions easier.
• Request directions on what is needed

Mark Rosenburg

• Uses [incr Tcl] all of the time. His work was aimed at composing as opposed to inheritance.

Dean Sheehan

• Had hand drawn slide showing:
  • ObjectTcl is for when you are using C++
  • Objective-Tcl is for when you are using Objective-C
  • [incr Tcl] and MIT Otcl is for OO at Tcl level.

David Wetherall

• Agrees with Dean.

Michael McLennan

• Also agrees with Dean (had prepared slide showing this)
• Disagrees that [incr Tcl] is not dynamic
• Can do one of following
  1. One class per object generated on the flow
  2. Use array (public or private) to implement slots
• Says really need name spaces in core with
  • public/private/protected access
  • import model
  • protection model
  • activation hooks

Pedja Bogdanovich

• Seamless integration with Objective-C
• No line between compiled and interpretive code
• Agrees with Mike that namespaces needed

Panel Agrees that John needs to add (for them to be dynamically loaded)

• Namespaces or at C level, need "unknown" hooks for commands and variables

References

• Widespread Uses
  • Web Pages
    • Incr Tcl
    • Incr Widgets
  • Included in Linux Slackware distribution
  • Integrated into Tcl compiler
    • mailing list
  • Integrated into Pathfinder browser
• Installed Base of Software
  • Wigwam
  • Itcl Widgets
  • Tree Widgets

Works In Progress - Round Table Discussion

Don Libs

• tkbiff
  • GUI mail notification
• autoexpect
  • Generates expect scripts from watching you

Larry Rowe and Brain Smith

• Tcl extensions to support continuous media
  • Supports simultaneous CM
  • Portable
  • Supports variety of media devices

Adam Sah

• Faster child of Tcl
  • Has pass-by-ref and pass-by-constant
  • Errors have two parts
    • Code
    • String

Ben Bederson

• Showed improved PAD++ with much improved zoom (high resolution)

David Keefe

• Talked about using Tcl/Tk in newspaper industry
  • Absolute deadlines
  • Limited to single binary placement

Stephen Karamatos

• The ConDoR Project
  • Combines WEB, E-mail, etc
  • Client Server implementation
    • Server
      • non Tcl
      • real time
      • dynamic objects
      • Objects store Tcl/Tk code
    • Clients Tcl/Tk

Maruo Comin

• GUI Builder called PanelBuilder

Scott Stewart

• TIGER CAD - a Tcl based CAD system

Northon Rodrigues

• Tcl based waveform analyzer & schematic editor

Stephen Uhler

• Hippo - a Tcl based Web browser
  • Extendible in Tcl
  • Faster than Mosaic or Netscape
  • A little C code to support HTTP
  • Supports multiple simultaneous fetches
  • Supports embedded Tcl/Tk

Gerald Lester

• About large projects using Tcl/Tk
  • Oil Platform control systems
    • Auger (done)
    • Mars (in-progress)
    • Ram-Powell (in-progress)
  • Electric Distribution
    • Reo de Janeiro (being installed)
  • Pipeline
    • Just started
  • Assist:
    • ESO
    • Lawrence Livermore National Labs