Namespaces Special Feature

Transcribed from the printed issue; not yet reviewed. Read it in the PDF of the issue, page 65

Namespaces are the most interesting new thing to happen to APL since nested arrays, and in this Vector we have tried to give you a cross-section of opinions on what they are good for, and where the pitfalls and limitations may lie.

This is still a very young technology, and it is up to you to influence its development. Please follow the advice in Duncan’s Editorial and experiment with these ideas as much as you can (maybe only on paper if you don’t have Dyalog 7 or the latest J release); then let us know what you think and Vector can help form a consensus on what is ‘just right’, what is harder to use than it should be, and what just got left out entirely.

Peter Donnelly works through a simple (but amusing) tutorial which will help you to grasp the basic ideas that objects can have hidden data. I believe that Vector can claim a publishing scoop here — we are the first APL magazine to reveal the co-ordinates of the Dyadic Duck.

Eric Lescasse has contributed a much more technical article which shows you how you can exploit namespaces effectively in building GUI systems.

Finally, Kimmo Kekäläinen offers some suggestions on using the session namespace ⎕SE to manage your utility set, and some warnings about the dangers of going too quickly into this new world. The feature ends with a return visit to Adrian Smith’s ‘Coast-to-Coast’ game to see how much of his APL code namespaces have replaced.