mirror of https://github.com/logos-co/scratch.git
34 lines
1.3 KiB
Common Lisp
34 lines
1.3 KiB
Common Lisp
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;;;; Constraint: you can't peek at the total without voting.
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;;;; N.b. this constraint is currently violated as anyone who has voted,
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;;;; may retain a reference to the current vote tallies
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;;; Simple multi-agents simulation with closures: after evaluation,
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;;; the environment contains a closure over an array specialized on
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;;; bits for accumulation of the storage
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(let* ((vote-types ;; a poor-man's typing system, but we only have two elements
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;; first value is an affirmative vote; the second a negative
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#(t nil))
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(length ;; total number of voters
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#+(or)
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(expt 2 8) ;; a safe value for testing
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(expt 2 33)) ;; challenging: on the order of 10^10
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(votes
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(make-array length :element-type 'cl:bit)))
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(defun consensus-agent-p (vote)
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(equalp vote (first vote-types)))
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(defun get-vote (id)
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(aref id votes))
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(defun record-vote (id vote)
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(incf
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(get-vote id)
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;; this is weird: there is an obvious logical shortcut, but does
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;; it express less is the question…
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(cond
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((if (consensus-agent-p vote)
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1
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-1)
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(t
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1))))
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(values votes ;; vote record is the primary value
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length))) ;; length is currently redundant, but in the future we may be able to adjust the underlying vector
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