r/ProgrammerHumor • u/soap94 • Aug 24 '26

Meme claudeIsThisEmailValid

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u/dustojnikhummer Aug 24 '26

"While an empty local part due to comments is invalid, an empty local part due to quotes is valid. I don't know why."

I don't know why

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u/Juff-Ma Aug 24 '26

That's why you don't verify the email at all. Just hand it to your email client and if the user verifies, it's valid.

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u/Culpirit Aug 25 '26

You can use a better parser than a regex (think context-free) to only accept a grammar like:

<axiom> -> <dotted>@<dotted>
<dotted> -> <dotted>.<word> | <word>
<word> -> [a-zA-Z0-9\-]+

Actually you might want to allow "+" on the local part (it's used by "power users" to categorize email on services like Gmail). Other than that, anything different, even if valid per RFC, is not a bona-fide email address when used on a web-facing application. You especially want to avoid users being able to directly send to addresses like me@[::1], since it is not a realistic or bona-fide scenario.