From e67ef3951c43b143093aec3bcbde975a686b36b2 Mon Sep 17 00:00:00 2001
From: Simon Forman <sforman@hushmail.com>
Date: Mon, 12 Aug 2019 20:59:02 -0700
Subject: [PATCH] Minor cleanup of the parser.

---
 thun/gnu-prolog/parser.pl | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/thun/gnu-prolog/parser.pl b/thun/gnu-prolog/parser.pl
index c953d03..4536cce 100644
--- a/thun/gnu-prolog/parser.pl
+++ b/thun/gnu-prolog/parser.pl
@@ -39,19 +39,14 @@ num(N) --> digits(Codes), !, { number_codes(N, Codes) }.
 
 % Groups of characters.
 
-chars([Ch|Rest]) --> char(Ch), chars(Rest).
-chars([Ch])      --> char(Ch).
-
-blanks --> blank, !, blanks.
-blanks --> [].
-
-digits([Ch|Rest]) --> digit(Ch), digits(Rest).
-digits([Ch])      --> digit(Ch).
+chars(Chars)   --> one_or_more(char, Chars).
+blanks         --> blank, !, blanks | [].
+digits(Digits) --> one_or_more(digit, Digits).
 
 % Character types.
 
-char(Ch)  --> [Ch], { nonvar(Ch), Ch \== 0'[, Ch \== 0'], between(33, 126, Ch) }.
-blank     --> [Ch], { nonvar(Ch), Ch =:= 32 ; between(9, 13, Ch) }.
+char(Ch)  --> [Ch], { nonvar(Ch), Ch =\= 0'[, Ch =\= 0'], between(33, 126, Ch) }.
+blank     --> [Ch], { nonvar(Ch),(Ch =:= 32 ; between(9, 13, Ch)) }.
 digit(Ch) --> [Ch], { nonvar(Ch), between(48, 57, Ch) }.
 
 
@@ -64,6 +59,10 @@ line(10,      []) :- !.  % break on new-lines.
 line(-1,   [eof]) :- !.  % break on EOF
 line(X, [X|Line]) :- get_code(Y), !, line(Y, Line).
 
+one_or_more(E, List) --> one_or_more_(List, E).
+
+one_or_more_([Ch|Rest], P) --> call(P, Ch), one_or_more_(Rest, P).
+one_or_more_([Ch],      P) --> call(P, Ch).
 
 /*