Constant autoloading in ruby on rails
summary
Explains how Active Support implements Ruby constant autoloading and development-mode code reloading by hooking into cons_missing hook, scanning autoload_paths directories, and tracking which constants and filenames load so reloading removes those constants and forces re-evaluation. Covers constant resolution rules, the trade-offs and failure modes (anonymous eval, nesting unknowns), the file update checker optimization, nonthread safety of on‑demand autoloading, and conventions required for predictable behavior.
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chapters (7)
- 0:00Start
- 0:12Constant Autoloading and Ruby on Rails
- 2:34Constant Assignment
- 9:31Constant Resolution Algorithms
- 15:16Constant Auto Loading
- 24:38Nesting
- 33:38File Update Checker
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