in reply to On Validating Email Addresses

This begs the question: "Why are you attempting to validate an email address"?

You wish to ensure that the user has typed his email address correctly because:

  1. As a service to your users--if they mistyped it, they will not receieve the information they have asked you for.

    If they really want that information, they will type it correctly.

  2. As a service to yourself--you wish to ensure that you can send them emails, before you allow them to progress to using your service.

    You don't wish to allow them to use your "service" (or have access to your information) without your being able to spa^H^H^H send them your very important and useful information.

    Again, if they want to receive whatever information you want to send them, they will type their email correctly.

    If they do not want to receive it, then typing some spurious addy, like a@b.com, will satisfy most simplistic checks. I don't know which poor blighter has the email addy a@b.com, but they must recieve a sh^H^H lot of junk they never asked for.

    If it is really commercially necessary to restrict your info/service to only those people that you can spam, the only(?) way, is to only provide access, once you recieve a confirmation to an email sent to the address supplied.

    Even this is easily bypassed by those that don't wish to receive "further correspondance", once they have satisfied your requirements.

  3. Other?

I first encountered this concept so loved by marketing people at Tandy/RadioShack. I was asked for my (land) address "before the till would accept my payment". As it happened, I was 3,500 miles from home at the time--which I explained.

"But the till won't accept payment without an address", I was told. "Where are you staying?".

"I don't know the address. I know how to get there, it was the first motel I encountered leaving the airport, but what the address is I have no idea. Hell, I'm not even sure what the name of the place is!".

"I have to have an address before I can complete the transaction".

"Okay, if any address will do, put your address in".

"Oh! I can't so that...".

Okay, please wait a minute while I check the address"..{I disappeared out of the shop for a couple of minutes}..."Okay. It's 7125"

"7125"

"1st Street"

"First Street".

"Utah"

"And the zip code?"

"Sorry, I don't know the zipcode".

"Okay, it should be able to look it....Hang on. That's the address of this shop!?".

"Did the till accept it?"

"Erm...Yes".

"Great! We're done then".

Examine what is said, not who speaks.
Silence betokens consent.
Love the truth but pardon error.

Replies are listed 'Best First'.
Re^2: On Validating Email Addresses
by dws (Chancellor) on Jan 04, 2005 at 04:53 UTC
    If they really want that information, they will type it correctly.

    I wish that were true. It's certainly not true for me. I mistyped my own email address the last time I submitted a bug and patch to CPAN, and didn't notice it until I re-read the submitted bug report. And I want to know if the patch gets accepted.

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Re^2: On Validating Email Addresses
by Thilosophy (Curate) on Jan 04, 2005 at 03:58 UTC
    If they really want that information, they will type it correctly.

    Since you cannot check if an email exists anyway, the most useful type of form data validation for emails is the one that catches typos, which is to have them enter the email twice and validate that they match (same as when you ask for password confirmation).

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      I wonder at those quite frequently.. And quite likely, if I typed it wrong the first time, then the second will be equally incorrect, since shift-tab, home, shift-end, ctrl-c, tab, ctrl-v is quicker to type than my address, which isnt one of the short ones.. :)

      C.

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Re^2: On Validating Email Addresses
by Juerd (Abbot) on Jan 04, 2005 at 11:49 UTC

    If they do not want to receive it, then typing some spurious addy, like a@b.com, will satisfy most simplistic checks. I don't know which poor blighter has the email addy a@b.com, but they must recieve a sh^H^H lot of junk they never asked for.

    I get spam at no@tnx.nl, which doesn't exist. But I get more spam even at aoeu%aoeu.nls/%/@/, which does exist. I feel sorry for the person who has asdf@asdf.com.

    Juerd # { site => 'juerd.nl', plp_site => 'plp.juerd.nl', do_not_use => 'spamtrap' }

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Re^2: [OT] On Validating Email Addresses
by trammell (Priest) on Jan 04, 2005 at 05:00 UTC
    This begs the question: "Why are you attempting to validate an email address"?

    Yeesh, that is one of my pet peeves. It may raise or suggest the question, but it certainly does not beg the question.

[reply]
      Yeesh, that is one of my pet peeves. It may raise or suggest the question, but it certainly does not beg the question.

      Of the 323,000 references to this phrase turned up by google, about 2 or 3 percent are people who have either unilaterally decided or have accepted the wisdom of some other, petitio principii-aware, usage nazi, that the only acceptable usage of this phrase is the classical rhetorical fallacy usage:

      To beg the question means 'to assume the truth of the very point being raised in a question'.

      The other 90%+, found in many highly respectable sources, including The New York Times, The Wall Street Journal, The Economist, The Times Literary Supplement, and even a hard-core academic journals, are usages similar to mine above, where the verb 'begs' is used as a substitute for the word 'entreat' or the phrase "ask earnestly for or of'.

      1. Language is a live, mutating entity and 'new' forms of usage are being adopted all the time.

        The only 'static' languages, are dead languages--like Latin.

      2. The classical usage is itself suspect.

        Let's try a little substitution--'beg' for 'assume':

        'to beg the truth of the very point being raised in a question'

        Does that make equivalent sense to the classical definition above? I think not.

        Or 'beg the point in a dispute' as meaning 'To take for granted without proof'?

        However, try:

        'That entreats the question...' or 'That implores the question "...", be asked. or 'That craves the question...'.

        I think those do!?

        Do you think it is possible that some ancient scholar made an error when translating from Latin or Greek to English or French at some point in history, and as a result, that nonsensical, idiomatic phrase has become enshrined in classical rhetorical teaching?

      3. Your suggested alternatives--"It may raise or suggest the question,..."--do not capture the essence of this usage.

        The implication of the phrase in the usage is not that the original text raised the question.

        It is that the original text didn't ask the question, when it probably should have asked.

        Whilst that is absolutely different from the classical usage, it does coincide with various other usages of the word 'beg' as a substitute for the word 'ask'.

        As in, 'I beg your forgiveness', or 'I beg to differ', or 'They begged the court's indulgance'.

      Examine what is said, not who speaks.
      Silence betokens consent.
      Love the truth but pardon error.
[reply]
        The other 90%+, found in many highly respectable sources,

        I agree that English is a living language. That doesn't mean that every pervasive meme is correct, however.

        Ninety percent of everything is crap. --Sturgeon's Law

        --
        [ e d @ h a l l e y . c c ]

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Re^2: On Validating Email Addresses
by saskaqueer (Friar) on Jan 05, 2005 at 03:16 UTC
    If they do not want to receive it, then typing some spurious addy, like a@b.com, will satisfy most simplistic checks. I don't know which poor blighter has the email addy a@b.com, but they must recieve a sh^H^H lot of junk they never asked for.

    A lot of people don't seem to know about m!^example\.(?:com|org|net)!. These domains are specifically meant for documentation and such, and therefore are perfect for fake email addresses (foobar@example.com for example). There are no MX records for these domains, nor is there anything listening on port 25. So as long as you're giving this value to a program that doesn't check for an MX record, these domains are perfect -- they are fake, and at the same time, you're not chancing giving someone's real email address and getting them spam'ed to death.

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[d/l]

      There are no MX records for these domains,

      I use me@privacy.net instead. See this for more info.

      The other approach, especially for one time registrations, is to use something like the Mailinator (unfortunately it seems to be down right now)

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        Try dodgeit.com - working for me.
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