first commit status: option and argument parsing, short aliases grouping, special values, hidden options

Option types: bool int, int-array, string, string-array, string-map, file, dir

common.go

@@ -0,0 +1,39 @@
+package cli
+
+import "fmt"
+
+func errMissingOptionValue(opt string) error {
+	return fmt.Errorf("option %q requires a value", opt)
+}
+
+func errOptionAlreadyDefined(opt string) error {
+	return fmt.Errorf("option name %q already used", opt)
+}
+
+func errRepeatArgAlreadyDefined(argName string) error {
+	return fmt.Errorf("repeat property already set for arg <%s>", argName)
+}
+
+func errMissingRequiredArg(argName string) error {
+	return fmt.Errorf("missing required arg <%s>", argName)
+}
+
+func errTooFewArguments(numRequired int) error {
+	return fmt.Errorf("too few arguments: ad least %d required", numRequired)
+}
+
+func errOptionNotFound(name string) error {
+	return fmt.Errorf("option %q not found", name)
+}
+
+func errInvalidOptionValue(name string, value any, optType string) error {
+	return fmt.Errorf("invalid value %v (%T) for option %q (%s)", value, value, name, optType)
+}
+
+func errIncompatibleOptions(currentOptName string, incompatibleOptName string) error {
+	return fmt.Errorf("option %q cannot specified together with option %q", currentOptName, incompatibleOptName)
+}
+
+func errUnknownOption(name string) error {
+	return fmt.Errorf("unknown option %q", name)
+}