Kdevelop4: Beyond C++...extending the Language Base

Kdevelop Unleashed.

KDevelop ... A Superb IDE in the making.

  • History and the road map of Kdevelop.
  • Good Code Completion
  • Great Code Navigation and features powered by Definition Use Chain
  • Efficient memory management.
  • The stats say it:

The Current Languages Support Status

  • C/C++
    • Class Wizard
    • Attribute/Method Wizard
    • Language Parser
    • Code Completion
    • Problem Reporter
    • Debugger
    • Source Code Formatter
  • Java
    • Class Wizard
    • Attribute/Method Wizard
    • ANTLR Language parser
    • Source Code Formatter
  • Python
    • Language Parser
    • Basic Extended Code Highlighting

Face-Off : Kick-Starting the Pre-Requisites.

  • a working checkout of KDE4 and Kdevelop4
    • The briefing.
  • The Lexer needs to be implemented/written
  • The Parser Needs to be in shape.
    • What should the grammar look like?
  • Parser Generators could be used Or a hand written pasrer.
  • Kdev-Pg is a handy tool.
    • Kdev-PG!! what is Kdev-Pg ?
    • What is fed into it ? How do i use it?
    • What does it produce? How do i use the output
    • What might be the shortcomings of using a parser-generator?

Diving into the language support.

  • Done with the parser for the language; what next?
    • Test, Test & Test again.
  • Write the Languagesupport headers and implementaions.
    • derived from Iplugin and Ilanguagesupport
    • can effectively use slots and signals to manage changes in the document status.
    • Returns:
      • The parsejob used by the the background parser to parse a given file.
      • The name of the language
      • The language being used.
  • The Language ParseJob:
    • Instigates the background parser, parse session and DU Chain for the document.

DU aka Definition Use Chain: the key to glory.

  • What is the Fuss all about?
  • How does it work?
  • What does it produce?
  • What use it is?
  • Extending the use beyond C++.
  • Viewing the outputs for it.

Extensions required in DUchain.

  •  EditorIntegrator  implementation
    • provides methods to integrate a text editor component
    • helps locate the position/range of the tokens.
  • ParseSession implementations.
  • Contextbuilder implementation.
  • Declarationbuilder implementation.
  • Usebuilder implementation


Putting the DUChain output in Use.

  • The DUChain has been built.
  • Use it for:
    • Code Highlighting
    • Advanced Syntax Highlighting
    • Code Completion
    • and many other features
  • PS: Only Syntax highlighting has been implemented for python by me.
  • Advanced Syntax Highlighting
    • adding custom coloring to declarations/definitions & uses.
  • Current DU Chain architecture that might make the use challenging.

Show .... Don't Tell

Working demonstrations, from my work on adding Python to Kdevelop4:-

  • Executing a working copy of Kdevelop4.
  • See the Python Plug-in in action, when a file is loaded.
    • On the terminal debug messages.
  • The DUChain works and shows the contexts created when a file is loaded.
    • As a Kdevelop4 Widget.
  • The Extended Code Highlighting after a *.py has been loaded.

Acknowledgments & References:

  • KDE 4 API reference available at
  • Python plug-in code for KDevelop4 available at

  • The C# & Java plug-ins for KDevelop4
  • Kdevelop 4 API reference available at

  • Thanks to:
    • 1
    • 2
    • 3
Copy of Presentation - Google Slides