;;; -*-scheme-*-

;;; GNU Mes --- Maxwell Equations of Software
;;; Copyright © 2016,2017,2018 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
;;;
;;; This file is part of GNU Mes.
;;;
;;; GNU Mes is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Mes 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 General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Mes.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;;; Implement core functionality that depends on implementation
;;; specifics of Mes cell types.

;;; Code:

(define cell:type-alist
  (list (cons <cell:bytes> (quote <cell:bytes>))
        (cons <cell:char> (quote <cell:char>))
        (cons <cell:closure> (quote <cell:closure>))
        (cons <cell:continuation> (quote <cell:continuation>))
        (cons <cell:keyword> (quote <cell:keyword>))
        (cons <cell:macro> (quote <cell:macro>))
        (cons <cell:number> (quote <cell:number>))
        (cons <cell:pair> (quote <cell:pair>))
        (cons <cell:ref> (quote <cell:ref>))
        (cons <cell:special> (quote <cell:special>))
        (cons <cell:string> (quote <cell:string>))
        (cons <cell:struct> (quote <cell:struct>))
        (cons <cell:symbol> (quote <cell:symbol>))
        (cons <cell:values> (quote <cell:values>))
        (cons <cell:variable> (quote <cell:variable>))
        (cons <cell:vector> (quote <cell:vector>))
        (cons <cell:broken-heart> (quote <cell:broken-heart>))))

(define (cell:type-name x)
  (cond ((assq (core:type x) cell:type-alist) => cdr)))

(define (bytes? x)
  (eq? (core:type x) <cell:bytes>))

(define (char? x)
  (and (eq? (core:type x) <cell:char>)
       (> (char->integer x) -1)))

(define (eof-object? x)
  (and (eq? (core:type x) <cell:char>)
       (= (char->integer x) -1)))

(define (closure? x)
  (eq? (core:type x) <cell:closure>))

(define (continuation? x)
  (eq? (core:type x) <cell:continuation>))

(define (keyword? x)
  (eq? (core:type x) <cell:keyword>))

(define (macro? x)
  (eq? (core:type x) <cell:macro>))

(define (number? x)
  (eq? (core:type x) <cell:number>))

(define (port? x)
  (eq? (core:type x) <cell:port>))

(define (procedure? p)
  (and (or (builtin? p)
           (and (pair? p) (eq? (car p) 'lambda))
           (closure? p))
       #t))

(define (special? x)
  (eq? (core:type x) <cell:special>))

(define (string? x)
  (eq? (core:type x) <cell:string>))

(define (struct? x)
  (eq? (core:type x) <cell:struct>))

(define (symbol? x)
  (eq? (core:type x) <cell:symbol>))

(define (values? x)
  (eq? (core:type x) <cell:values>))

(define (variable? x)
  (eq? (core:type x) <cell:variable>))

(define (variable-global? x)
  (core:cdr x))

(define (vector? x)
  (eq? (core:type x) <cell:vector>))

(define (broken-heart? x)
  (eq? (core:type x) <cell:broken-heart>))

(define (atom? x)
  (not (pair? x)))

(define (boolean? x)
  (or (eq? x #f) (eq? x #t)))


;;; core: accessors
(define (string . lst)
  (list->string lst))

(define (keyword->list s)
  (string->list (keyword->string s)))

(define (symbol->list s)
  (string->list (symbol->string s)))