HACKER Q&A
📣 hairywalt

What is the origin of the term "edge case"?


For reasons, I've become interested in the background to the term "edge case". I'd presumed it was old school engineering terminology that had been ported over to software.

But searching on Google Books etc. all the uses that fit the modern meaning are related to programming/software testing, and even those examples are relatively recent.

Is this correct or am I missing something?

  👤 082349872349872 Accepted Answer ✓
https://books.google.com/ngrams/graph?content=corner+case%2C...

suggests it's a low-dimension version of "corner case", which I believe comes from aerospace*. (both spike in 1947-1957, which, albeit possible, seems early for a software origin)

* compare "coffin corner": https://books.google.com/ngrams/graph?content=corner+case%2C...

👤 ahazred8ta
Apparently it started out in aviation engineering, referring to unusual behavior at the edge of the flight envelope. Related to 'corner case'.