Recursion has never been invented: A tale of intrigue
summary
Claim: recursion is discovered not invented, and the Y combinator is rebuilt live in JavaScript. The session shows working code for factorial and Fibonacci, demonstrates stack overflow for deep recursion, and instruments Node and browsers to inspect call frames. It compares proper tail calls vs removed engine support (only Safari/old Node kept it), implements trampolines and thunks to avoid overflow, and gives a runnable Y combinator that makes anonymous recursion without identifiers.
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chapters (12)
- 0:00Start
- 1:22What Is Recursion
- 2:39The Factorial Function
- 4:35The Fibonacci Function
- 7:00Design Recursive Algorithms
- 13:31Stack Trace
- 26:13Syntactic Tail Calls
- 28:34Shadow Stacks
- 29:01The History of Recursion
- 43:03What Is the Fixed Point of a Function
- 44:48Easiest Way of Delaying the Execution of a Function
- 53:44The Y Combinator
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