Devise not respecting config.email_regexp
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I wanted to change the regex that defines valid emails in my application. To check whether the regex was working I tried to start with something easy like 

    config.email_regexp = /\d+/

when that didn't work, I thought maybe my knowledge of ruby's regex sytax was off and tried what I thought was a super simple regex 

    config.email_regexp = /a/

While changing the following DOES have an impact on the passwords allowed, the previous to lines seem to have no effect.

    config.password_length = 2..128

What else should I do in order to modify the regex validating emails? (after I made each of these modifications I restarted the server to make sure the changes were picked up.)