if … then … else had to be invented!
summary
Traces the claim that the familiar if then else is an invention: conditionals start as wired decisions on ENIAC 1946, evolve into 1949 conditional jumps and Fortran’s three-way if, Flow‑Matic’s otherwise, divergent German and American Algol drafts, McCarthy’s LISP conditional expression with otherwise, and Claus Samuelson’s introduction of else leading to Algol 60’s unified form in 1959–60. The concrete artifacts, keywords, and grammar changes are shown and the final form succeeds, becoming the dominant design.
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chapters (6)
- 0:00Start
- 1:09Eniac
- 1:52Conditional Jump
- 5:32Boolean Expressions
- 7:36Conditional Expressions
- 9:04Indentation
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