Joseph Ferano
dfd64d89ea
Copying a snippet into HTML is where a documented language stops being the real one. Each block on the page is a program here with its recorded output beside it, and check.sh is what says the page is still true after a change.
25 lines
674 B
Plaintext
25 lines
674 B
Plaintext
(defstruct AssetMissing [id i32])
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(defvar cleanups i64)
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(defn load [n i32] i32
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(signal (AssetMissing {:id n}))
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100)
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(defn middle [n i32] i32
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(defer (set cleanups (+ cleanups 1))) ; runs on the transfer too
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(+ (load n) 1))
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(defn fetch [n i32] i32
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(restart-case (middle n) ; its value if nothing transfers
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(use-placeholder [] -1)
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(retry [] 7)))
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(defn main []
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(print-i64 (i64 (fetch 1))) (newline) ; 101 — nothing handled it
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(handler-bind [(AssetMissing [c] (invoke-restart 'use-placeholder))]
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(print-i64 (i64 (fetch 2))) (newline)) ; -1
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(print-i64 cleanups) (newline)) ; 2 — the defer ran both times
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