Inter-File Arrows

In multi-file programs, the source (or destination) of an arrow may sometimes refer to a program point in a separate file. In this case MrSpidey draws an arrow originating (or terminating) in the left margin of the program: see figure 4.2. If a margin arrow is painted red, then it refers to an expression in a file that has not yet been loaded, and clicking on the arrow provides the option to load the file. A blue margin arrow refers to an expression in a file that has been loaded. Clicking on a blue arrow provides the option to zoom to and highlight the term at the other end of the arrow, as shown in figure 4.3. These facilities are useful for following the flow of values through multi-file programs.

Figure 4.2: Source in another loaded file

Figure 4.3: The highlighted source in the other file