From 7edbb540bdf1c7d18ce43299f06884a6e0545f82 Mon Sep 17 00:00:00 2001
From: Mark Thom <markjordanthom@gmail.com>
Date: Sun, 24 Feb 2019 13:10:31 -0700
Subject: [PATCH] use can_be and must_be in library(between)

---
 src/prolog/lib/between.pl | 20 +++++++++++++-------
 src/prolog/machine/mod.rs |  6 +++---
 src/prolog/write.rs       |  2 +-
 3 files changed, 17 insertions(+), 11 deletions(-)

diff --git a/src/prolog/lib/between.pl b/src/prolog/lib/between.pl
index e7167ca7..730e590e 100644
--- a/src/prolog/lib/between.pl
+++ b/src/prolog/lib/between.pl
@@ -3,6 +3,7 @@
 %% TODO: numlist/5.
 
 :- use_module(library(lists), [length/2]).
+:- use_module(library(error)).
 
 between(Lower, Upper, Lower) :-
     Lower =< Upper.
@@ -19,7 +20,9 @@ enumerate_nats(I0, N) :-
 gen_nat(N) :-
     integer(N), !, N >= 0.
 gen_nat(N) :-
-    var(N), enumerate_nats(0, N).
+    var(N), !, enumerate_nats(0, N).
+gen_nat(N) :-
+    throw(error(type_error(integer, N), gen_nat/1)).
 
 enumerate_ints(I, I).
 enumerate_ints(I0, N) :-
@@ -32,7 +35,9 @@ enumerate_ints(I0, N) :-
 gen_int(N) :-
     integer(N), !.
 gen_int(N) :-
-    var(N), enumerate_ints(0, N).
+    var(N), !, enumerate_ints(0, N).
+gen_int(N) :-
+    throw(error(type_error(integer, N), gen_int/1)).
 
 repeat_integer(N) :-
     N > 0.
@@ -40,7 +45,7 @@ repeat_integer(N0) :-
     N0 > 0, N1 is N0 - 1, repeat_integer(N1).
 
 repeat(N) :-
-    integer(N), N > 0, repeat_integer(N).
+    must_be(integer, N), N > 0, repeat_integer(N).
 
 numlist(Upper, List) :-
     (  integer(Upper) -> findall(X, between(1, Upper, X), List)
@@ -48,14 +53,14 @@ numlist(Upper, List) :-
     ).
 
 diag_nats(M, N, M, N).
+diag_nats(M, 0, M1, N1) :-
+    !,
+    M0 is M+1,
+    diag_nats(0, M0, M1, N1).
 diag_nats(M, N, M1, N1) :-
-    N > 0, !,
     M0 is M+1,
     N0 is N-1,
     diag_nats(M0, N0, M1, N1).
-diag_nats(M, 0, M1, N1) :-
-    M0 is M+1,
-    diag_nats(0, M0, M1, N1).
 
 diag_nats(0, 0).
 diag_nats(M, N) :-
@@ -82,6 +87,7 @@ diag_ints(M, N) :-
     diag_ints(M0, N0, M, N).
 
 gen_ints(L, U) :-
+    can_be(integer, L), can_be(integer, U),
     (  integer(L), integer(U), !
     ;  integer(L) -> gen_int(U)
     ;  integer(U) -> gen_int(L)
diff --git a/src/prolog/machine/mod.rs b/src/prolog/machine/mod.rs
index b0eeb266..c2567c4e 100644
--- a/src/prolog/machine/mod.rs
+++ b/src/prolog/machine/mod.rs
@@ -312,10 +312,10 @@ impl SubModuleUser for IndexStore {
 }
 
 static BUILTINS: &str = include_str!("../lib/builtins.pl");
-static BETWEEN: &str  = include_str!("../lib/between.pl");
 static LISTS: &str    = include_str!("../lib/lists.pl");
 static QUEUES: &str   = include_str!("../lib/queues.pl");
 static ERROR: &str    = include_str!("../lib/error.pl");
+static BETWEEN: &str  = include_str!("../lib/between.pl");
 static TERMS: &str    = include_str!("../lib/terms.pl");
 static DCGS: &str     = include_str!("../lib/dcgs.pl");
 static ATTS: &str     = include_str!("../lib/atts.pl");
@@ -343,10 +343,10 @@ impl Machine {
     }
 
     fn compile_libraries(&mut self) {
-        compile_user_module(self, LISTS.as_bytes());
-        compile_user_module(self, BETWEEN.as_bytes());
+        compile_user_module(self, LISTS.as_bytes());        
         compile_user_module(self, QUEUES.as_bytes());
         compile_user_module(self, ERROR.as_bytes());
+        compile_user_module(self, BETWEEN.as_bytes());
 	compile_user_module(self, TERMS.as_bytes());
         compile_user_module(self, DCGS.as_bytes());
         compile_user_module(self, ATTS.as_bytes());
diff --git a/src/prolog/write.rs b/src/prolog/write.rs
index 6b39d382..206fc87c 100644
--- a/src/prolog/write.rs
+++ b/src/prolog/write.rs
@@ -389,7 +389,7 @@ pub fn print(wam: &mut Machine, result: EvalSession) {
                 let attr_goals = wam.attribute_goals(&heap_locs);
 
                 if !attr_goals.is_empty() {
-                    write!(raw_stdout, "\r\n{}\r", attr_goals).unwrap();
+                    write!(raw_stdout, "\r\n{}\r\n", attr_goals).unwrap();
                 }
 
                 if !wam.or_stack_is_empty() {
-- 
2.54.0