COMPSCI 732 Software Tools Techniques Vi TABa L

COMPSCI 732 Software Tools & Techniques Vi. TABa. L : A Visual Language Supporting Design by Tool Abstraction By John C. Grundy and John G. Hosking Group 10

Vi. TABa. L : : Visual Tool Abstraction Based Language l l For designing systems supporting functional evolution. Tool abstraction (TA) domain involving units of functionality called toolies, which share a pool of abstract data structures (ADSs). Interaction via event propagation. Example of a system modeled by TA shown in Figure 1 and expressed in a Vi. TABa. L event propagation view in Figure 2. Figure 1: KWIC, A word indexing system modeled by TA. Figure 2 : KWIC system expressed as Vi. TABa. L event propagation view.

Vi. TABa. L : : views l l l Graphical metaphor and textual metaphor used. High level of closeness of mapping. Targeted end users are software programmers. Good level of visibility via multiple views (hierarchical and multiple perspectives), but also this leads to hidden dependencies. Figure 3: multiple views of complex system. Figure 4: Hierarchical toolie specification. Figure 5: Textual event response for KWIC toolies.

Vi. TABa. L : : views l l l No problem of viscosity. Toolies can be reused easily. As the system evolve, no extra code is needed for toolies or ADSs which are not directly affected by the change. Good level of progressive evaluation as programmers can build a complex system into parts and/or to split a complex system into smaller parts for easier debugging. Language not too diffused. Not many symbols required to express a meaning.

Vi. TABa. L : : visualisation l l Supports visual debugging. Provides good level of roleexpressiveness with animated event propagation views and cues to provide more information about components of the system. Figure 6: Visual debugging of Vi. TABa. L systems [1].