Skip to main content

GHood -- Graphical Visualisation and Animation of Haskell Object Observations

Reinke, Claus (2001) GHood -- Graphical Visualisation and Animation of Haskell Object Observations. In: Hinze, Ralf, ed. ACM Sigplan Haskell Workshop, Firenze, Italy. Electronic Notes in Theoretical Computer Science , 59. Elsevier Science (KAR id:13558)

Language: English
Download (494kB) Preview
Language: English
Download (1MB) Preview


As a possible extension to his Hood, Andy Gill has described the ``dynamic viewing of structures'', stepping through observations instead of accumulating them into a static view. Starting from this idea, we have implemented and released an animation back-end for Hood, called Instead of the dynamic textual visualisation based on pretty-printing proposed in, our back-end features a dynamic graphical visualisation, based on a simple tree layout algorithm. This paper reviews the main aspects of Hood, gives a brief introduction to GHood's features and summarises our experience so far. The visualisation of program behaviour via animations of data structure observations has uses for program comprehension and exposition, in development, debugging and education. We find that the graphical structure facilitates orientation even when textual labels are no longer readable due to scaling, suggesting advantages over a purely textual visualisation. A novel application area is opened by the use of GHood as an applet on webpages -- discussions of Haskell program behaviour, e.g., in educational online material or in explanations of functional algorithms, can now easily be augmented with graphical animations of the issues being discussed.

Item Type: Conference or workshop item (Paper)
Additional information: Preliminary Proceedings have appeared as Technical Report UU-CS-2001-23, Institute of Information and Computing Sciences, Utrecht University. Final proceedings to appear in ENTCS.
Uncontrolled keywords: Haskell, program visualisation, debugging
Subjects: Q Science > QA Mathematics (inc Computing science) > QA 76 Software, computer programming,
Divisions: Faculties > Sciences > School of Computing > Theoretical Computing Group
Depositing User: Mark Wheadon
Date Deposited: 24 Nov 2008 17:58 UTC
Last Modified: 28 May 2019 13:50 UTC
Resource URI: (The current URI for this page, for reference purposes)
  • Depositors only (login required):


Downloads per month over past year