Sinap types a run-time language for data-description

Sinap IDE is an editor for graph-based programming languages (as distinct from textbased). To facilitate versatility in Sinap IDE it was necessary to design a language (Sinap's Type System) to generically describe families of well-formed cyclic data structures. This language can be used to maintain run-time information about values that would not otherwise be present. It is used in Sinap IDE to store attributed graphs representing computer programs, allowing Sinap to specialize the user interface to that graph. This thesis presents a model for Sinap's Type System. This model is a formal description of the behavior of the Type System library analogous to models of programming languages such as Lua or Standard ML.