globals: Fix math operations returning argument list on single arg

src/CMakeLists.txt

@@ -59,6 +59,7 @@ functionaltest("function-mutable-capture")
 functionaltest("map")
 functionaltest("deconstruct")
 functionaltest("shadowing")
+functionaltest("mathops")
 
 install(TARGETS apfl DESTINATION lib)
 install(TARGETS apfl-bin DESTINATION bin)

src/functional-tests/mathops.at

@@ -0,0 +1,17 @@
+===== script =====
+print (+ 1 2)
+print (+ 1 2 3 4)
+print (- 1)
+print (- 1 2)
+print (- 1 2 3)
+print (* 1 2 3)
+print (/ 1 2 4)
+
+===== output =====
+3
+10
+-1
+-1
+-4
+6
+0.125

src/globals.c

@@ -101,7 +101,7 @@ impl_eq(apfl_ctx ctx)
         apfl_get_list_member_by_index(ctx, 0, 0);                                            \
         apfl_number num = apfl_get_number(ctx, -1);                                          \
         if (len == 1) {                                                                      \
-            single(num);                                                                     \
+            apfl_push_number(ctx, single(num));                                              \
             return;                                                                          \
         }                                                                                    \
                                                                                              \