general callback function to just get entity guids

[coldtrick]

It would be nice if there was a general callback function for elgg_get_entities*() which just returns the guids.

If we want to do this now, every plugin would have to write their own callback function. Maybe this could be something for core?

function name something like entity_row_to_guid()???

[brettp]

I've used this often enough to reluctantly agree. Looking at the use cases:

• Serializing a list of guids / annotation IDs
• Building SQL IN clauses.
• Passing guids to external apps.

I'm reluctant because I think the need to do this speaks somewhat to limitations in the current data model and helper functions.