mes: #<eof> is not a character.

* module/mes/display.mes (display):
* module/mes/type-0.mes (char?): -1 is not a character.
  (eof-object?): New function.
* tests/base.test ("#<eof>"): Test it.
* module/mes/scm.mes (eof-object?): Remove.
  (unread-char): Return character (WAS: integer).

module/mes/display.mes

@@ -1,7 +1,7 @@
 ;;; -*-scheme-*-
 
 ;;; Mes --- Maxwell Equations of Software
-;;; Copyright © 2016,2017 Jan Nieuwenhuizen <janneke@gnu.org>
+;;; Copyright © 2016,2017,2018 Jan Nieuwenhuizen <janneke@gnu.org>
 ;;;
 ;;; This file is part of Mes.
 ;;;
@@ -62,10 +62,11 @@
     (define (d x cont? sep)
       (for-each (cut write-char <> port) (string->list sep))
       (cond
+       ((eof-object? x)
+        (display "#<eof>" port))
        ((char? x)
         (if (not write?) (write-char x port)
-            (let ((name (and=> (assq x '((#\*eof* . *eof*)
-                                         (#\nul . nul)
+            (let ((name (and=> (assq x '((#\nul . nul)
                                          (#\alarm . alarm)
                                          (#\backspace . backspace)
                                          (#\tab . tab)

module/mes/scm.mes

@@ -82,10 +82,6 @@
 
 (define integer? number?)
 
-(define (eof-object? x)
-  (or (and (number? x) (= x -1))
-      (and (char? x) (eof-object? (char->integer x)))))
-
 (if (not (defined? 'peek-char))
     (define (peek-char)
       (integer->char (peek-byte))))
@@ -96,7 +92,7 @@
 
 (if (not (defined? 'unread-char))
     (define (unread-char c)
-      (unread-byte (char->integer c))))
+      (integer->char (unread-byte (char->integer c)))))
 
 (define (assq-set! alist key val)
   (let ((entry (assq key alist)))

module/mes/type-0.mes

@@ -1,7 +1,7 @@
 ;;; -*-scheme-*-
 
 ;;; Mes --- Maxwell Equations of Software
-;;; Copyright © 2016,2017 Jan Nieuwenhuizen <janneke@gnu.org>
+;;; Copyright © 2016,2017,2018 Jan Nieuwenhuizen <janneke@gnu.org>
 ;;;
 ;;; This file is part of Mes.
 ;;;
@@ -62,7 +62,12 @@
   (cond ((assq (core:type x) cell:type-alist) => cdr)))
 
 (define (char? x)
-  (eq? (core:type x) <cell:char>))
+  (and (eq? (core:type x) <cell:char>)
+       (>= (char->integer x) 0)))
+
+(define (eof-object? x)
+  (and (eq? (core:type x) <cell:char>)
+       (= (char->integer x) -1)))
 
 (define (closure? x)
   (eq? (core:type x) <cell:closure>))

tests/base.test

@@ -9,7 +9,7 @@ exit $?
 ;;; -*-scheme-*-
 
 ;;; Mes --- Maxwell Equations of Software
-;;; Copyright © 2016 Jan Nieuwenhuizen <janneke@gnu.org>
+;;; Copyright © 2016,2018 Jan Nieuwenhuizen <janneke@gnu.org>
 ;;;
 ;;; This file is part of Mes.
 ;;;
@@ -110,4 +110,8 @@ exit $?
         (begin (set! seen? #t)
                (cont 2)))))
 
+(if (not guile?)
+    (pass-if-not "#<eof>"
+                 (char? (integer->char -1))))
+
 (result 'report)