You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
117 lines
4.0 KiB
Scheme
117 lines
4.0 KiB
Scheme
;;; Copyright 2022 Edward L. Platt
|
|
;;;
|
|
;;; Licensed under the Apache License, Version 2.0 (the "License");
|
|
;;; you may not use this file except in compliance with the License.
|
|
;;; You may obtain a copy of the License at
|
|
;;;
|
|
;;; http://www.apache.org/licenses/LICENSE-2.0
|
|
;;;
|
|
;;; Unless required by applicable law or agreed to in writing, software
|
|
;;; distributed under the License is distributed on an "AS IS" BASIS,
|
|
;;; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
;;; See the License for the specific language governing permissions and
|
|
;;; limitations under the License.
|
|
|
|
(define-module (deliberate)
|
|
#:use-module (srfi srfi-1)
|
|
#:use-module (goblins)
|
|
#:use-module (goblins vrun)
|
|
#:use-module (goblins actor-lib methods)
|
|
#:use-module (deliberate utils)
|
|
#:use-module (deliberate preference)
|
|
#:export (^deliberation ^deliberation-info ^ranked-choice-vote ^ranked-ballot ^ranked-preference))
|
|
|
|
;; Constructor for ^deliberation-info
|
|
;; Information about a deliberation
|
|
;;
|
|
;; Parameters:
|
|
;; title: Title of the deliberation
|
|
;;
|
|
;; Messages:
|
|
;; get-title: Return the title
|
|
;; set-title: new-title: Set the title to new-title
|
|
;;
|
|
(define (^deliberation-info bcom title)
|
|
(methods
|
|
((get-title) title)
|
|
((set-title) (bcom (^decision bcom title)))
|
|
))
|
|
|
|
;; Constructor for ^deliberation
|
|
;; A deliberation with multiple possible alternative outcomes
|
|
;;
|
|
;; Parameters:
|
|
;; title: Title of the deliberation
|
|
;;
|
|
;; Messages:
|
|
;; get-title: Return the title
|
|
;; set-title: new-title: Set the title to new-title
|
|
;; add-alternative alt: Add a new alternative (possible outcome)
|
|
;; represented by the string alt.
|
|
;; get-alternatives: Return a list of all alteratives
|
|
;;
|
|
(define (^deliberation _bcom title)
|
|
(let (
|
|
(info (spawn ^deliberation-info title))
|
|
(alternatives (spawn ^alternatives title))
|
|
)
|
|
(methods
|
|
((get-title) ($ info 'get-title))
|
|
((set-title new-title) ($ info 'set-title new-title))
|
|
((add-alternative alt) ($ alternatives 'add alt))
|
|
((get-alternatives) ($ alternatives 'alternatives))
|
|
)))
|
|
|
|
;; Constructor for ^ranked-ballot
|
|
;; Allow one constituent to update their rank-order preference
|
|
;;
|
|
;; Parameters:
|
|
;; deliberation-info: ^deliberation-info relevnt to this ballot
|
|
;; alternatives: ^alternatives object representing possible outcomes
|
|
;;
|
|
;; Messages:
|
|
;; update-vote f: Updates the constituent's vote on this ballot.
|
|
;; The procedure f is called with one parameter: the list of available
|
|
;; alternatives. f must return a list of rank preferences
|
|
;; (1 is most preferred) corresponding to the alternatives componentwise.
|
|
;; get-preference: Returns a ^ranked-preference associated with this ballot.
|
|
;; The object is attenuated to be read-only.
|
|
;;
|
|
(define (^ranked-ballot _bcom deliberation-info alternatives)
|
|
(define ranking (spawn ^ranked-preference '()))
|
|
(methods
|
|
((update-vote f)
|
|
(let* ((alt-list ($ alternatives 'get))
|
|
(ranks (f alt-list))
|
|
(new-ranking (reorder alt-list ranks)))
|
|
($ ranking 'set new-ranking)))
|
|
((get-preference) (spawn ^attenuated ranking '(get get-rank)))
|
|
))
|
|
|
|
;; Constructor for ^ranked-choice-vote
|
|
;; A updateable vote using ranked choice preferences
|
|
;;
|
|
;; Parameters:
|
|
;; deliberation-info: deliberation-info relevant to this vote
|
|
;; alternatives: cell containig list of altenatives
|
|
;;
|
|
;; Messages:
|
|
;; get-ballots: Return the list of ballots
|
|
;; add-ballot: Add a new ballot to this vote and return it
|
|
;;
|
|
(define (^ranked-choice-vote bcom deliberation-info alternatives)
|
|
(define ballots (spawn ^cell '()))
|
|
(methods
|
|
((get-ballots) ($ ballots 'get))
|
|
((add-ballot)
|
|
(define ballot (spawn ^ranked-ballot deliberation-info alternatives))
|
|
(define old-ballots ($ ballots 'get))
|
|
($ ballots 'set (cons ballot old-ballots))
|
|
ballot)
|
|
((get-profile)
|
|
;; This is a very space-heavy representation
|
|
;; Would be better to use a hashmap keyed on rankings with counts as values
|
|
(map (lambda (ballot) ($ ($ ballot 'get-preference) 'get))
|
|
ballots))
|
|
))
|