Ads Quote by Philip Greenspun
“Greenspun's Tenth Rule of Programming: any sufficiently complicated C or Fortran program contains an ad hoc informally-specified bug-ridden slow implementation of half of Common Lisp.”
About This Quote
Source Book: *The Art of Computer Programming* (reference), 1990
Describes how complex legacy code often hides inefficient, ad‑hoc implementations, especially when mimicking higher‑level language features.
In simple terms: Complex code hides slow, messy solutions.
Key Takeaway
Beware hidden inefficiencies in legacy systems.
Themes
programming
legacy code
complexity
efficiency
Mood
analytical
critical
Type
technical
educational
When to use this quote
- code review
- system refactoring
- performance tuning
- language migration
Key Concepts
software engineering
abstraction
bug patterns
Questions to Reflect On
- What part of your codebase is most opaque?
- How can you simplify a slow module?
A Different Perspective
May overgeneralize to all languages; not all bugs are ad‑hoc.
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