Design Note #0 - KISS Principle

Revised: 32 January 2007
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SG - Design

Prime Directives:

Keep It Small and Simple (KISS) ==> need to partition into modules.
Divide and Conquer

Strive for High Cohesiveness in each module ==> focus on a single activity.
Public processing model should be simple even though there may be complex internal details.

Strive for loose coupling ==> refer to abstractions, not implementations.
Use Interfaces to support plug-in instances of any class derived from the interface.

Examples:

  1. The Tokenizer module, in Parser folder collects tokens for analysis of grammatical constructs found in a source code file.
    It supports cohesiveness by hiding complex character manipulations in a private helper functions.
  2. The Parser module, in Parser folder illustrates how binding to interfaces, Rule and Action, allows any instance of a class, derived from the interface, Rule for example, to be plugged into an instance of Parser, modifying the way it carries out its work.