note
hatter
I use localisation not just for error messages, but also for bodies of text (primarily for use on a website) So I use the same policy for both types of text - short, meaningful, programmer-oriented names. invalid_email should be clearer to someone whose first language isn't english that email_address_typed_incorrectly, which might be what you tell the english user, but isn't technically spot-on.
<br>
<br>
<code>the hatter</code>
263023
263023