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Paste # 89285
2019-05-23 08:09:36

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Using mutable keys in equal?-based hash tables

  1. #lang racket
  2. (define o (box 1))
  3. (define h (hash-set (hash) o 123))
  4. (set-box! o 2)
  5. (hash-ref h o)
  6. ; hash-ref: no value found for key
  7. ;   key: '#&2
  8. ; [,bt for context]

=>

hash-ref: no value found for key

  key: '#&2