Figure 3 : an example of form generated by the program of figure 1
By pressing the SUBMIT button, the form data is passed to a CGI program on a server, which processes it.
Our experiments indicate that a general purpose data-flow visual programming environment like VIPERS can be effectively used by skilled users to digest Web information in an easy manner. The program described above was used as a testing exercise with a group of six engineering students. All the testers were able to assemble the application from the modules (blocks) and macromodules shown in the figure.
It is worth noting how the visual programming approach described here could be used for rapid program prototyping as well. Indeed, once a program has been built, it could be advantageously translated into a single script (for example in Tcl), which can be used without need for the VIPERS visual interface.
We are now developing an on-line version of the VIPERS system, which will allow to build visual Internet applications by simply connecting to a proper site and assembling ready-made blocks taken from various libraries. Block execution will occur both locally or, when needed, on remote machines.
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