Re: [xdi] PLEASE VOTE: XDI attribute instance syntax preference question

[Drummond Reed <drummond.reed@xdi.org>]

Markus, very good points. I would argue, however, that's it's not entirely "consistent attribute syntax" vs. "consistent instance syntax" for this reason: under option B, the following two rules still hold true:

1. All instances (whether entity instances or attribute instances) will be prefixed with either ! (unordered) or # (ordered).
2. All attributes will be enclosed in chevrons.

So while it's true that if we adopt option B, not all instances will START with a ! or # character, they are still PREFIXED with a ! or # character.

For that reason, I find it more consistent to enclose all attributes (whether classes, instances, or singletons) in chevrons, just as we enclose all classes (whether entities or attributes) in square brackets.

So I too vote for the change, i.e., Option B.

On Mon, Aug 12, 2013 at 1:29 AM, Markus Sabadello <markus.sabadello@xdi.org> wrote:

Pretty hard choice. I think the arguments about additional characters and about looking back or ahead are negligible. To me it really seems to be just about cosmetics and not about functionality.

While the change would make attribute syntax always consistent, it would make instance syntax inconsistent, i.e. entity instances and attribute instances would then look differently.
You can only have one of the two, either consistent attribute syntax, or consistent instance syntax.

Anyway, I vote for the change, i.e. Option B.

Markus

On Mon, Aug 12, 2013 at 9:53 AM, Drummond Reed <drummond.reed@xdi.org> wrote:

From the last TC meeting I have an action item to post this poll to the mailing list.

Please respond by indicating whether for the syntax for instances of an attribute class you prefer:

1. Option A below.
2. Option B below.
3. No preference.

OPTION A

This is our current syntax which does NOT include chevrons around instances of an attribute class.

=drummond+home[<+tel>]!1234&/&/"+1-206-222-2222"

=drummond+home[<+tel>]!:uuid:f81d4fae-7dec-11d0-a765-00a0c91e0001&/&/"+1-206-111-1111"

=drummond+home[<+tel>]#3&/&/"+1-206-222-2222"

OPTION B

This change would include chevrons around instances of an attribute class.

=drummond+home[<+tel>]<!1234>&/&/"+1-206-222-2222"

=drummond+home[<+tel>]<!:uuid:f81d4fae-7dec-11d0-a765-00a0c91e0001>&/&/"+1-206-111-1111"

=drummond+home[<+tel>]<#3>&/&/"+1-206-222-2222"

NOTES

• The only difference between the two is the addition of chevrons around instances of an attribute class.
• The arguments FOR:
• It will simplify XDI syntax because there be one consistent rule: all attributes ALWAYS must be in chevrons (whether classes, instances, or singletons).
• It does not require "looking back" an additional arc to determine if an arc represents an attribute instance or an entity instance.
• The arguments AGAINST:
• It adds two more characters to the XDI address of an instance of an attribute class.
• It requires looking at the second character to distinguish an attribute of an attribute class from an instance of an attribute class. (Both would now start with <, so you have to look at the second character— ! or # would indicate an instance, + or $ an attribute).