From: Markus Triska <triska@metalevel.at>
Date: Sun, 7 Jun 2020 22:07:24 +0000 (+0200)
Subject: type check for ~d and ~D specifiers
X-Git-Tag: v0.8.127~52^2
X-Git-Url: https://git.sagredo.dev/?a=commitdiff_plain;h=c22816de08fc1682ea2f3d48b5167c141608a92a;p=scryer-prolog.git

type check for ~d and ~D specifiers
---

diff --git a/src/prolog/lib/format.pl b/src/prolog/lib/format.pl
index d91fdc91..e8be4df3 100644
--- a/src/prolog/lib/format.pl
+++ b/src/prolog/lib/format.pl
@@ -172,9 +172,11 @@ cells([~,a|Fs], [Arg|Args], Tab, Es) --> !,
         { atom_chars(Arg, Chars) },
         cells(Fs, Args, Tab, [chars(Chars)|Es]).
 cells([~|Fs0], Args0, Tab, Es) -->
-        { numeric_argument(Fs0, Num, [d|Fs], Args0, [Arg|Args]) },
+        { numeric_argument(Fs0, Num, [d|Fs], Args0, [Arg0|Args]) },
         !,
-        { format_number_chars(Arg, Cs0) },
+        { Arg is Arg0, % evaluate compound expression
+          must_be(integer, Arg),
+          number_chars(Arg, Cs0) },
         (   { Num =:= 0 } -> { Cs = Cs0 }
         ;   { length(Cs0, L),
               (   L =< Num ->