1 files changed, 86 insertions, 0 deletions
diff --git a/core/flags/parsing.odin b/core/flags/parsing.odin
new file mode 100644
index 000000000..68f3ea56e
--- /dev/null
+++ b/core/flags/parsing.odin
@@ -0,0 +1,86 @@
+package flags
+
+import "core:strings"
+_ :: strings
+
+@(private)
+parse_one_arg :: proc(data: ^$T, arg: string, pos: ^int, set_args: ^[dynamic]string) -> (err: Error) {
+	arg := arg
+
+	if strings.has_prefix(arg, "-") {
+		arg = arg[1:]
+
+		if colon := strings.index_byte(arg, ':'); colon != -1 {
+			flag := arg[:colon]
+			arg = arg[1 + colon:]
+
+			if equals := strings.index_byte(arg, '='); equals != -1 {
+				// -map:key=value
+				key := arg[:equals]
+				value := arg[1 + equals:]
+				set_key_value(data, flag, key, value) or_return
+				append(set_args, flag)
+			} else {
+				// -flag:option
+				set_option(data, flag, arg) or_return
+				append(set_args, flag)
+			}
+
+		} else if equals := strings.index_byte(arg, '='); equals != -1 {
+			// -flag=option, alternative syntax
+			flag := arg[:equals]
+			arg = arg[1 + equals:]
+
+			set_option(data, flag, arg) or_return
+			append(set_args, flag)
+		} else {
+			// -flag
+			set_flag(data, arg) or_return
+			append(set_args, arg)
+		}
+
+	} else {
+		// positional
+		err = add_positional(data, pos^, arg)
+		pos^ += 1
+	}
+
+	return
+}
+
+// Parse a slice of command-line arguments into an annotated struct.
+//
+// If `validate_args` is set, an error will be returned if all required
+// arguments are not set. This step is only completed if there were no errors
+// from parsing.
+//
+// If `strict` is set, an error will cause parsing to stop and the procedure
+// will return with the message. Otherwise, parsing will continue and only the
+// last error will be returned.
+parse :: proc(data: ^$T, args: []string, validate_args: bool = true, strict: bool = true) -> (err: Error) {
+	// For checking required arguments.
+	set_args: [dynamic]string
+	defer delete(set_args)
+
+	// Positional argument tracker.
+	pos := 0
+
+	if strict {
+		for arg in args {
+			parse_one_arg(data, arg, &pos, &set_args) or_return
+		}
+	} else {
+		for arg in args {
+			this_error := parse_one_arg(data, arg, &pos, &set_args)
+			if this_error != nil {
+				err = this_error
+			}
+		}
+	}
+
+	if err == nil && validate_args {
+		return validate(data, pos, set_args[:])
+	}
+
+	return err
+}