+is(join(":","-4".."0") , "-4:-3:-2:-1:0");
+is(join(":","-4".."-0") , "-4:-3:-2:-1:0");
+is(join(":","-4\n".."0\n") , "-4:-3:-2:-1:0");
+is(join(":","-4\n".."-0\n"), "-4:-3:-2:-1:0");
+
+# undef should be treated as 0 for numerical range
+is(join(":",undef..2), '0:1:2');
+is(join(":",-2..undef), '-2:-1:0');
+is(join(":",undef..'2'), '0:1:2');
+is(join(":",'-2'..undef), '-2:-1:0');
+
+# undef should be treated as "" for magical range
+is(join(":", map "[$_]", "".."B"), '[]');
+is(join(":", map "[$_]", undef.."B"), '[]');
+is(join(":", map "[$_]", "B"..""), '');
+is(join(":", map "[$_]", "B"..undef), '');
+
+# undef..undef used to segfault
+is(join(":", map "[$_]", undef..undef), '[]');
+
+# also test undef in foreach loops
+@foo=(); push @foo, $_ for undef..2;
+is(join(":", @foo), '0:1:2');
+
+@foo=(); push @foo, $_ for -2..undef;
+is(join(":", @foo), '-2:-1:0');
+
+@foo=(); push @foo, $_ for undef..'2';
+is(join(":", @foo), '0:1:2');
+
+@foo=(); push @foo, $_ for '-2'..undef;
+is(join(":", @foo), '-2:-1:0');
+
+@foo=(); push @foo, $_ for undef.."B";
+is(join(":", map "[$_]", @foo), '[]');
+
+@foo=(); push @foo, $_ for "".."B";
+is(join(":", map "[$_]", @foo), '[]');
+
+@foo=(); push @foo, $_ for "B"..undef;
+is(join(":", map "[$_]", @foo), '');
+
+@foo=(); push @foo, $_ for "B".."";
+is(join(":", map "[$_]", @foo), '');
+
+@foo=(); push @foo, $_ for undef..undef;
+is(join(":", map "[$_]", @foo), '[]');
+
+# again with magic
+{
+ my @a = (1..3);
+ @foo=(); push @foo, $_ for undef..$#a;
+ is(join(":", @foo), '0:1:2');
+}
+{
+ my @a = ();
+ @foo=(); push @foo, $_ for $#a..undef;
+ is(join(":", @foo), '-1:0');
+}
+{
+ local $1;
+ "2" =~ /(.+)/;
+ @foo=(); push @foo, $_ for undef..$1;
+ is(join(":", @foo), '0:1:2');
+}
+{
+ local $1;
+ "-2" =~ /(.+)/;
+ @foo=(); push @foo, $_ for $1..undef;
+ is(join(":", @foo), '-2:-1:0');
+}
+{
+ local $1;
+ "B" =~ /(.+)/;
+ @foo=(); push @foo, $_ for undef..$1;
+ is(join(":", map "[$_]", @foo), '[]');
+}
+{
+ local $1;
+ "B" =~ /(.+)/;
+ @foo=(); push @foo, $_ for ""..$1;
+ is(join(":", map "[$_]", @foo), '[]');
+}
+{
+ local $1;
+ "B" =~ /(.+)/;
+ @foo=(); push @foo, $_ for $1..undef;
+ is(join(":", map "[$_]", @foo), '');
+}
+{
+ local $1;
+ "B" =~ /(.+)/;
+ @foo=(); push @foo, $_ for $1.."";
+ is(join(":", map "[$_]", @foo), '');
+}