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Use-cases are the bane of orthogonality

• From: "Costello, Roger L." <costello@mitre.org>
• To: "xml-dev@lists.xml.org" <xml-dev@lists.xml.org>
• Date: Sun, 7 Jun 2015 20:34:52 +0000

Hi Folks,

[Definition] Bane: a thing that ruins or spoils.

[Definition] Orthogonality: if a tool is orthogonal, it can be added, replaced, or removed, in favor of better tools, without screwing everything else up. The classic example is Unix command line tools: you have one tool for getting the contents of a disk (dd), another for filtering lines from the file (grep), another for writing those lines to a file (cat), etc. These can all be mixed and matched at will. [1]

Michael Kay wrote this extraordinary statement: [2]

 	Use-cases are the bane of orthogonality. Any system with 
	good orthogonality can do things for which it is very difficult 
	to find a use case. Design focused excessively on use-cases 
	leads to a lack of orthogonality.

Then, without focusing on use-cases, how does one approach design? Is this the right approach: Develop a few use-cases for inspiration and then work on creating simple components that can be connected to any other component?

/Roger

[1] See the answer from Lee B on this stack overflow post: http://stackoverflow.com/questions/1527393/what-is-orthogonality 

[2] http://lists.xml.org/archives/xml-dev/201506/msg00007.html 

• Follow-Ups:
  • Re: Use-cases are the bane of orthogonality
    • From: Rick Jelliffe <rjelliffe@allette.com.au>
  • Re: Use-cases are the bane of orthogonality
    • From: Michael Kay <mike@saxonica.com>
  • Re: Use-cases are the bane of orthogonality
    • From: Michael Kay <mike@saxonica.com>