Meme Media Technology in Higher Education: The Recursive Function Theory Case Study - Webble Technology - page 115

5 Didactic Needs Reflected in Webble Technology
In section 2 we described the challenges which arise by teaching the recursive
function theory to students. Out of these challenges, some didactic needs result to
the learning program. This chapter gives an overview about these needs based
on the planned program features. Figure 3 shows a fictional screenshot from
the finished program. The red rectangles illustrate the five main segments each
marked with a red number for the following description.
Fig. 3. Fictional screenshot from the finished learning program
1. If you want to create more complex primitive recursive functions you need
a way to add the six ground functions: projection, successor, constant, sub-
stitution, primitive recursion and minimum operator (see section 3). The
first segment GroundFuntions shows a menu which provides a simple way to
achieve this task. The user can add the ground functions as PRF-Webbles
to the Workspace (see figure 3 number 2) by simply clicking on the corre-
sponding item.
2. The second segment Workspace is the main operating window. The users
can change the attributes and values of the six ground functions and create
new functions by dragging them together. When assembling new functions
it is checked if they fit together. For example, when a projection has three
input values, it needs a substitution or primitive recursion functions which
has a placeholder for a input function with three input values. After the users
have created a new function, they can “group“ it to hide the inner functions