use traditional controller tool to generate code

vendor/github.com/gobuffalo/flect/underscore.go

@@ -0,0 +1,34 @@
+package flect
+
+import (
+	"strings"
+	"unicode"
+)
+
+// Underscore a string
+//	bob dylan = bob_dylan
+//	Nice to see you! = nice_to_see_you
+//	widgetID = widget_id
+func Underscore(s string) string {
+	return New(s).Underscore().String()
+}
+
+// Underscore a string
+//	bob dylan = bob_dylan
+//	Nice to see you! = nice_to_see_you
+//	widgetID = widget_id
+func (i Ident) Underscore() Ident {
+	var out []string
+	for _, part := range i.Parts {
+		var x string
+		for _, c := range part {
+			if unicode.IsLetter(c) || unicode.IsDigit(c) {
+				x += string(c)
+			}
+		}
+		if x != "" {
+			out = append(out, x)
+		}
+	}
+	return New(strings.ToLower(strings.Join(out, "_")))
+}