diff --git a/src/types.c b/src/types.c
index bbf5c36..b8adf83 100644
--- a/src/types.c
+++ b/src/types.c
@@ -149,8 +149,47 @@ void printGroundValue(GroundValue* gv) {
             printf("<function>");
             break;
         }
-        default: {
-            printf("FIXME");
+        case STRUCTVAL: {
+            printf("<struct fields: { ");
+            for (size_t i = 0; i < gv->data.structVal->size; i++) {
+                if (i != 0) {
+                    printf(", ");
+                }
+                printf("%s: ", gv->data.structVal->fields[i].id);
+                if (gv->data.structVal->fields[i].value.type == STRING) {
+                    printf("\"");
+                    printGroundValue(&gv->data.structVal->fields[i].value);
+                    printf("\"");
+                } else {
+                    printGroundValue(&gv->data.structVal->fields[i].value);
+                }
+            }
+            printf(" }>");
+            break;
+        }
+        case CUSTOM: {
+            printf("<object fields: { ");
+            for (size_t i = 0; i < gv->customType->size; i++) {
+                if (i != 0) {
+                    printf(", ");
+                }
+                printf("%s: ", gv->customType->fields[i].id);
+                GroundObjectField* field = findField(*gv->data.customVal, gv->customType->fields[i].id);
+                if (field == NULL) {
+                    printf("<missing>");
+                } else {
+                    printGroundValue(&field->value);
+                }
+            }
+            printf(" }>");
+            break;
+        }
+        case ERROR: {
+            printf("<error type: %s, what: %s>", gv->data.errorVal.type, gv->data.errorVal.what);
+            break;
+        }
+        case NONE: {
+            printf("<none>");
             break;
         }
     }