1 files changed, 5 insertions, 0 deletions
diff --git a/parse.go b/parse.go
index aee60e7..a85419f 100644
--- a/parse.go
+++ b/parse.go
@@ -360,6 +360,11 @@ func cmdFromStruct(name string, dest path, t reflect.Type) (*command, error) {
 			case strings.HasPrefix(key, "--"):
 				spec.long = key[2:]
 			case strings.HasPrefix(key, "-"):
+				if len(key) != 2 {
+					errs = append(errs, fmt.Sprintf("%s.%s: short arguments must be one character only",
+						t.Name(), field.Name))
+					return false
+				}
 				spec.short = key[1:]
 			case key == "required":
 				spec.required = true