! Empty range
{ 0 } [ 1 0 1 <range> sum ] unit-test
+
+{ t } [ 4 4 10 2 <range> in? ] unit-test
+{ t } [ 6 4 10 2 <range> in? ] unit-test
+{ t } [ 10 4 10 2 <range> in? ] unit-test
+{ t } [ -6 4 -10 -2 <range> in? ] unit-test
+{ t } [ 6 10 4 -1 <range> in? ] unit-test
+
+{ f } [ 5 4 10 2 <range> in? ] unit-test
+{ f } [ 3 4 10 2 <range> in? ] unit-test
+{ f } [ 4.0 4 10 2 <range> in? ] unit-test
+{ f } [ 6.0 4 10 2 <range> in? ] unit-test
+{ f } [ 10.0 4 10 2 <range> in? ] unit-test
+
+{ { } } [ 1 8 2 <range> 2 9 2 <range> intersect >array ] unit-test
+{ { } } [ 1 8 2 <range> 8 1 -2 <range> intersect >array ] unit-test
+{ { } } [ 1 -9 1 <range> 1 8 1 <range> intersect >array ] unit-test
+{ { 13 19 25 31 37 43 49 } } [
+ 1 100 3 <range> 11 50 2 <range> intersect >array ] unit-test
+{ { 6 } } [
+ 6 7 1 <range> 6 -20 -4 <range> intersect >array ] unit-test
+
+{ f } [ 1 8 2 <range> 2 9 2 <range> intersects? ] unit-test
+{ f } [ 1 8 2 <range> 8 1 -2 <range> intersects? ] unit-test
+{ f } [ 1 -9 1 <range> 1 8 1 <range> intersects? ] unit-test
+{ t } [ 1 100 3 <range> 11 50 2 <range> intersects? ] unit-test
+{ t } [ 6 7 1 <range> 6 -20 -4 <range> intersects? ] unit-test
+
+{ t } [ 6 9 2 <range> 6 8 2 <range> set= ] unit-test
+{ t } [ 2 9 2 <range> 8 1 -2 <range> set= ] unit-test
+{ t } [ 9 0 3 <range> 4 8 -2 <range> set= ] unit-test
+{ f } [ 1 8 1 <range> 1 8 2 <range> set= ] unit-test
+
+{ t } [ 3 10 4 <range> 1 10 2 <range> subset? ] unit-test
+{ t } [ 1 0 1 <range> 10 2 1 <range> subset? ] unit-test
+{ f } [ 1 10 2 <range> 3 10 4 <range> subset? ] unit-test
\ No newline at end of file