Spreadsheets are Code

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" summary

Claim: spreadsheets are Turing complete — a full Turing machine is implemented in Excel formulas and visualized, and a working selection sort in Excel is built using only formulas. Research shows only one in three spreadsheets have documentation, spreadsheets pass through about 12 people over ~5 years, and ~10% of formulas act as ad‑hoc tests. Tools include a grammar/parser on GitHub, a refactoring tool and the Expector test plugin (running in a user study) that detect smells and generate runnable tests.

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" chapters (29)

1. 0:00Introduction
2. 0:15Spreadsheets are Code
3. 0:49Programming Domains
4. 1:13Why Spreadsheets
5. 2:06Turing Machine
6. 4:32Live Programming
7. 5:23Functional Programming
8. 6:07Everyone knows this stuff
9. 6:54Selection Sort
10. 9:16Dollar Sign
11. 9:53Swap
12. 11:18Copy
13. 11:53Minimum
14. 12:36Offsets
15. 13:31Pop Quiz
16. 14:09Intersection
17. 18:22Poetry
18. 19:39Row Function
19. 20:13Indirect Function
20. 21:43Previous Row
21. 22:37Index Swap
22. 23:18The Idea
23. 25:13The Conclusion
24. 25:37Examples
25. 25:53refactoring
26. 28:53test formulas
27. 31:17coverage
28. 34:52user test
29. 35:26summary

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