types.rkt

;;  zKanren: MicroKanren with Constraints and noto
;;  Copyright (C) 2017  Zaoqi

;;  This program is free software: you can redistribute it and/or modify
;;  it under the terms of the GNU Affero General Public License as published
;;  by the Free Software Foundation, either version 3 of the License, or
;;  (at your option) any later version.

;;  This program is distributed in the hope that it will be useful,
;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;;  GNU Affero General Public License for more details.

;;  You should have received a copy of the GNU Affero General Public License
;;  along with this program.  If not, see <http://www.gnu.org/licenses/>.
#lang racket
(provide
 (contract-out (struct state
                 [(g (listof goal?))
                  (c hash?)
                  (hg set-weak?)]))
 append-hg
 )
(require "goal.rkt")

#| [Goal] → Hash ID ConstraintsV → WeakSet Goal → State |#
(struct state (g c hg))

#| [Goal] → WeakSet Goal → WeakSet Goal |#
(define/contract (append-hg gs hg)
  ((listof goal?) set-weak? . -> . set-weak?)
  (list->weak-set (append gs (set->list hg))))