Online resource catalogs edge cases and flaws in programming type systems

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A website titled 'Counterexamples in Type Systems' documents known failure cases and surprising behaviors found across various programming language type systems. The resource, originally compiled in 2021, serves as a reference for researchers, language designers, and developers. It highlights scenarios where type systems behave unexpectedly or unsoundly, helping practitioners understand their limitations. The site resurfaced on Hacker News, attracting attention from the programming language theory community.

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