Add support for TextUnmarshaler

forms.go

@@ -1,6 +1,7 @@
 package forms
 
 import (
+	"encoding"
 	"reflect"
 	"strconv"
 	"strings"
@@ -26,13 +27,21 @@ func decode(form Values, rv reflect.Value, prefix string) {
 			continue
 		}
 
-		// TODO: Add custom interface
-
 		fe := ft.Type
 		if fe.Kind() == reflect.Ptr {
 			fe = fe.Elem()
 		}
 
+		if tu, ok := fv.Addr().Interface().(encoding.TextUnmarshaler); ok {
+			v, ok := form[getName(ft, prefix)]
+			if !ok || len(v) == 0 {
+				continue
+			}
+
+			tu.UnmarshalText([]byte(v[0]))
+			continue
+		}
+
 		if fe.Kind() == reflect.Struct {
 			if fv.Kind() == reflect.Ptr {
 				found := false