One regret I have about ActivityPub is that navigating reverse chronological collections is really error-prone.
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One regret I have about ActivityPub is that navigating reverse chronological collections is really error-prone. "first", "last", "next" and "prev" mean the opposite of what you think they mean, so it's easy to get mixed up and navigate things the wrong way.
It's too late to change now, but I could see adding some synonyms for these properties, like "newest", "oldest", "older" and "newer", to make it easier to do the navigation code.
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One regret I have about ActivityPub is that navigating reverse chronological collections is really error-prone. "first", "last", "next" and "prev" mean the opposite of what you think they mean, so it's easy to get mixed up and navigate things the wrong way.
It's too late to change now, but I could see adding some synonyms for these properties, like "newest", "oldest", "older" and "newer", to make it easier to do the navigation code.
@evan could this be fixed by a future version? Or given that the set is not overlapping I guess they could be provided concurrently for compatibility?
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undefined julian shared this topic
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One regret I have about ActivityPub is that navigating reverse chronological collections is really error-prone. "first", "last", "next" and "prev" mean the opposite of what you think they mean, so it's easy to get mixed up and navigate things the wrong way.
It's too late to change now, but I could see adding some synonyms for these properties, like "newest", "oldest", "older" and "newer", to make it easier to do the navigation code.
evan@cosocial.ca what about
after? Using paginated collections is easy, but could be problematic if the set changes while you are navigating.Using
afteris a little more complicated but much more reliable in terms of getting exactly the next set of items. -
@julian Pages should be real containers, not slices of the collection like "last 25 items".
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System shared this topic
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@evan could this be fixed by a future version? Or given that the set is not overlapping I guess they could be provided concurrently for compatibility?
@flancian It's an egregiously backwards-incompatible change, so probably no.
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@flancian It's an egregiously backwards-incompatible change, so probably no.
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@julian Pages should be real containers, not slices of the collection like "last 25 items".
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evan@cosocial.ca what about after? Using paginated collections is easy, but could be problematic if the set changes while you are navigating.
Using after is a little more complicated but much more reliable in terms of getting exactly the next set of items.
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@evan could this be fixed by a future version? Or given that the set is not overlapping I guess they could be provided concurrently for compatibility?
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One regret I have about ActivityPub is that navigating reverse chronological collections is really error-prone. "first", "last", "next" and "prev" mean the opposite of what you think they mean, so it's easy to get mixed up and navigate things the wrong way.
It's too late to change now, but I could see adding some synonyms for these properties, like "newest", "oldest", "older" and "newer", to make it easier to do the navigation code.
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@thisismissem@activitypub.space Ah, I seem to have misread the code. I was confused by Mastodon serving its own instance actor from /actor. Thanks for the clarification!
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Where are you seeing this?
Mastodon does serve its instance actor as /actor, however it doesn't actually track the "instance actor" as a concept, because there's actually no way to do so. fep-2677 doesn't define one, it just says the instance actor must be an Application, and adds a reference to that actor to NodeInfo.
That is, from the actor document alone, there is no way to know if it is the "instance actor" (remembering too that AP doesn't have any notion of an "instance" or "server")
Likewise, internally in Mastodon, the instance actor record will have the ID of -99.
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<del datetime="2025-10-12T21:34:00+09:00">TIL: #Mastodon specifically treats actor URIs with the pattern https://<domain>/actor as instance actors.</del> <ins datetime="2025-10-12T21:34:00+09:00">Turns out I misread the code. 😅</ins>
#fedidev #ActivityPub
