1 files changed, 45 insertions, 0 deletions
diff --git a/core/flags/validation.odin b/core/flags/validation.odin
new file mode 100644
index 000000000..c5cad8c7a
--- /dev/null
+++ b/core/flags/validation.odin
@@ -0,0 +1,45 @@
+package flags
+
+import "core:fmt"
+import "core:reflect"
+import "core:strconv"
+
+_ :: fmt
+_ :: reflect
+_ :: strconv
+
+// Validate that all the required arguments are set.
+validate :: proc(data: ^$T, max_pos: int, set_args: []string) -> Error {
+	fields := reflect.struct_fields_zipped(T)
+
+	check_fields: for field in fields {
+		tag := reflect.struct_tag_lookup(field.tag, TAG_ARGS) or_continue
+		if _, ok := get_struct_subtag(tag, SUBTAG_REQUIRED); ok {
+			was_set := false
+
+			// Check if it was set by name.
+			check_set_args: for set_arg in set_args {
+				if get_field_name(field) == set_arg {
+					was_set = true
+					break check_set_args
+				}
+			}
+
+			// Check if it was set by position.
+			if pos, has_pos := get_struct_subtag(tag, SUBTAG_POS); has_pos {
+				value, value_ok := strconv.parse_int(pos)
+				if value < max_pos {
+					was_set = true
+				}
+			}
+
+			if !was_set {
+				return Validation_Error {
+					fmt.tprintf("required argument `%s` was not set", field.name),
+				}
+			}
+		}
+	}
+
+	return nil
+}