[HN Gopher] Falsehoods Programmers Believe About Phone Numbers
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Falsehoods Programmers Believe About Phone Numbers
Author : umitkaanusta
Score : 27 points
Date : 2024-07-07 16:56 UTC (6 hours ago)
(HTM) web link (github.com)
(TXT) w3m dump (github.com)
| LatticeAnimal wrote:
| > In New Zealand, non-urgent traffic incidents can be reported by
| calling *555 from a mobile phone. Alpha characters may also be
| used in phone numbers, such as in 1-800-Flowers.
|
| Is this true? Do carriers actually accept [a-zA-Z] in their phone
| numbers? (if so, how are they encoded?). I couldn't find any
| reference to this elsewhere.
|
| I had assumed that advertisement-numbers like `1-800-Flowers` had
| to be translated by a person when they entered the number on
| their phone via their keypad.
| 1659447091 wrote:
| Given the context `Falsehoods Programmers Believe`, I think it
| is referring to how one validates a number submitted from a
| form (but maybe there are devices like this?). So, if a flowers
| company signs up and wants to list their number as
| 1-800-Flowers they would get a validation error on many sites.
| heelix wrote:
| When I'm interviewing, I'll usually start with something
| simple with an input that is a phone number and the first
| 'questionable' input I'll hand them is 1-800-FLOWERS and ask
| how they are handling it. There are a lot of interesting edge
| cases with phone numbers. None super tricky , but it makes
| for an interesting first set of how someone thinks
| chmod775 wrote:
| Just today a delivery service wanted to send an SMS to validate
| my phone number, so I was forced to use a mobile phone number
| rather than landline. Landline often makes more sense, because
| usually they'd call to reach someone in the household the item is
| being delivered to, not a specific person. Other delivery
| services _require_ a landline number, which sucks for people who
| don 't have one.
|
| Some services limit you to one account per phone number. Not only
| are there 5 numbers that route to my card (probably common given
| that this was a local providers standard offering some time ago),
| once I even got a one-time token for some account a previous
| owner of a number was apparently trying to reset. It helpfully
| informed me which service it was for, so I could have likely used
| the fact that I now control that number to take over their
| account.
|
| Using phone numbers for 2FA/account resets is worse than e-mail,
| even ignoring the fact how vulnerable telephone networks are to
| spoofing/intercepts.
| BugsJustFindMe wrote:
| 1-800-FLOWERS is _not_ a phone _number_. The phone _number_ is
| 1-800-356-9377. FLOWERS is just a mnemonic device called a phone
| _word_ (https://en.wikipedia.org/wiki/Phoneword).
|
| Maybe the document should be called falsehoods programmers
| believe about what people will provide when asked for their phone
| number.
| aidenn0 wrote:
| What about e.g. KLondike-5-1234?
| simonblack wrote:
| The "Falsehoods Programmers Believe about ..." series is well
| worth reading every six months or so.
|
| Invariably you forget one of the pitfalls.
|
| The things that annoys me about "Falsehoods Programmers Believe
| about Email Addresses" is that one person can have several email
| addresses, or use one email address for several different uses,
| so using an email address as a login to a website account can get
| really, really messy.
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(page generated 2024-07-07 23:01 UTC)