1 files changed, 2 insertions, 4 deletions
diff --git a/acf/model/field.lua b/acf/model/field.lua
index d4e934c..362c7ab 100644
--- a/acf/model/field.lua
+++ b/acf/model/field.lua
@@ -32,9 +32,7 @@ end
 
 function M.Member:auto_ui_name(name)
    if not name then return end
-   return string.gsub(
-      string.upper(string.sub(name, 1, 1))..string.sub(name, 2), '-', ' '
-   )
+   return (name:sub(1, 1):upper()..name:sub(2)):gsub('-', ' ')
 end
 
 function M.Member:meta(context)
@@ -129,7 +127,7 @@ end
 
 function M.String:validate(context, value)
    super(self, M.String):validate(context, value)
-   if self['max-length'] and string.len(value) > self['max-length'] then
+   if self['max-length'] and value:len() > self['max-length'] then
       raise(context.path, 'Maximum length exceeded')
    end
 end