History of Design Principles

Given that I am going to be writing blog entries on design principles I thought I would start by making some introductory remarks on the history of said principles.

The first thinking about computer programming focused on data structures and algorithms.  The approach to these was and is mostly mathematical.  There is no inherent attention paid to the implementation in this discipline.

Programming design principles derive almost universally from the work around structured programming.  Object Orientation is a development of linguistic structures and their application to package the design principles developed by the structured programming movement.

The opening salvo in the movement was Dijkstra's letter (retitled by Wirth), "Go-to Statement Considered Harmful".  This lead fairly directly to a programming style and languages that used if, for, while and like constructs.  These principles are pretty much universally accepted now.

This sufficed at the lowest level of code construction, but further principles were required when considering deisgn at a slightly higher level.  The question here is not what happens inside a subroutine (to use an early word) but how to decide what to do in a subroutine and how they should communicate.

The basis of this will be the subject of my next post.