Design and implementation of a visual syntax for Smalltalk

The visual syntax described in this thesis defines a visual representation of Smalltalk code. It provides a clear and predictable presentation of the messages and "flow" of objects within a method. This syntax has been implemented in a visual browser that allows methods to be viewed and edited either graphically or as text. An important feature of this syntax is its compatibility with existing Smalltalk textual code. Methods defined visually or as text are both translated into the same intermediate representation and can be converted into either form. Thus existing methods created using text can be viewed and modified using the visual browser and methods created visually can also be edited as text. The use of this visual syntax and the supporting browser eliminates certain types of programming errors while providing a visual presentation of the semantics and logic of the method. It remains to be proven that this will be advantageous for training and application development. The syntax and tools described in this thesis will make an objective evaluation of this hypothesis possible.