Proposal to replace documented syntax for telephone extensions

[Jofban]

@Minh_Nguyen

I guess we need to decide first of all whether phone=* should optimize for human readability or machine readability.

My opinion is clear, phone=* should be for human consumption and manual entry, ideally showing exactly what the user has to type in. This exludes mnemonics who help the user remember the number, but the user is expected to type in numbers instead of letters.

@Minh_Nguyen

openstreetmap-website has a routine that converts already RFC 3966–conformant dial strings to tel: URIs by prepending the tel: scheme, as if the value is not quite machine-readable, but not quite non-machine-readable either:

Some phone numbers happen to be in tel: format, that doesn’t preclude the phone:tel tag. For clarification, like in other cases, we could stipulate that

if the number in phone is not in the tel: format, specify also phone:tel with the number in tel: format.

This way we avoid duplication. Note however that the tel: format disallows whitespace, hence the post-processing in your excerpt. We could allow those as exceptions.

@Minh_Nguyen

an extension technically doesn’t say how long [or in what way] to pause

Where the number cannot be called fully automatically due to this pause, perhaps a subkey phone:pause could provide clarification and enable proper user instructions. E.g.

phone=+1-888-828-4798 ext. 2334|+1-777-717-3687 ext. 1223
phone:tel=+1-888-828-4798,,2334|
phone:pause=2s|operator

The first number needs a 2s delay at least, the second number needs the user to say the extension to an operator. Since the second number isn’t fully automatic, I have excluded it from phone:tel.
What do you think?