1 files changed, 23 insertions, 0 deletions
diff --git a/util.go b/util.go
index 6b5049e..c8ed617 100644
--- a/util.go
+++ b/util.go
@@ -1,5 +1,12 @@
 package main
 
+// Minimal Error type... is there a better way?
+type Error string
+
+func (e Error) Error() string {
+	return string(e)
+}
+
 type EmailAddress string
 type Password string
 type Url string
@@ -7,3 +14,19 @@ type Url string
 // "Slug" string with limited ASCII character set, good for URLs.
 // Lowercase alphanumeric plus '_' allowed. 
 type ShortName string
+
+func isShortName(s string) bool {
+	for i, r := range s {
+		switch {
+		case '0' <= r && '9' >= r && i > 0:
+			continue
+		case 'a' <= r && 'z' >= r:
+			continue
+		case r == '_' && i > 0:
+			continue
+		default:
+			return false
+		}
+	}
+	return true
+}