hashtags: Difference between revisions
Tantek.com (talk | contribs) (→Brainstorming: put Twitter's regex link at top, note non-international (english-only) limitation of the short regexes) |
Tantek.com (talk | contribs) (→Brainstorming: subheads, add hashtags for tags with spaces for discoverability) |
||
| Line 56: | Line 56: | ||
== Brainstorming == | == Brainstorming == | ||
: [[#]] | |||
=== Regex === | === Regex === | ||
Revision as of 20:43, 2 January 2019
This article is a stub. You can help the IndieWeb wiki by expanding it.
hashtags are the use of the hash "#" symbol followed immediately by a word/phrase/abbreviation to explicitly denote a topic inline in a post. Popularized on Twitter, they're now everpresent on Instagram and other silos where they link to aggregations of posts inside those silos with those tags.
This page is specifically about hashtags. For general concept of tags and tagging content, see:
Markup
Use rel=tag on hashtag links. If you're using h-entry (you really should be ;) then use p-category as well.
Discovery
How do we discover indieweb posts tagged with a particular tag? It’s a problem well suited to centralised hubs.
Could we get services like tagboard to start indexing indieweb posts, not just posts in silos?
IndieWeb examples
Aaron Parecki
Aaron Parecki uses p3k on aaronparecki.com to auto-link hashtags on his posts to his own tag aggregation page since 2013-03-08.
Barnaby Walters
Barnaby Walters uses Taproot on waterpigs.co.uk to auto-link to a /tags page containing a list of links to content which is tagged with that tag (as per hypermedia API design, example) since 2012-09-22. This probably needs some js/iframe goodness to pull that content in --Waterpigs.co.uk 05:57, 19 April 2013 (PDT)
FAQ
Autolinking hashtags
Where should hashtags in posts be auto-linked to?
Link them to a page on your site which aggregates posts tagged with that tag. It’s fine for this to just redirect to, for example, a google search of your site for that tag, but by always linking to a URL you control you can improve it/self-host it later.
Silo support
Silos that support hashtag aggregation on their own content.
Single post-type hashtag aggregations:
- Twitter - notes (with embedded media, but not displayed by default, you have to twiddle them open)
- Flickr - photos (and videos, but they don't play on tag aggregation pages, so effectively they're just images as well - poster-images from videos)
Composite post-type hashtag aggregations:
- Tumblr - Tumbler has an amazing display of hetergenous post types in a single tag aggregation grid.
- e.g. http://www.tumblr.com/tagged/cortexiphan shows a tag grid of the following post types
- photo, including animated GIFs
- video
- note
- quote
- post with embedded media (photo or video), at least partially displayed by default
Limitations
It appears that most platforms/silos limit hashtags to:
- _a-zA-Z0-9 characters
- Twitter, max length 139 (since Tweet length is 140)
- Twitter max promoted trend (hashtag) is 20.[1]
- most sites disallow hashtags that are just numbers (exception: Instagram allows them)
- some sites disallow hashtags that start with numbers (exception: Twitter near the end of 2009 started supporting hashtags that start with numbers per the increased frequency of use, e.g. #2009resolution.)
See also:
Brainstorming
hashtags for tags with spaces
Tantek Çelik: some thoughts here for now: Falcon#tags_with_spaces
person tag in plain text
Regex
Check out Twitter's regex: https://github.com/twitter/twitter-text/blob/master/js/twitter-text.js#L135-L141
The following are a coarse approximations which will miss numerous international (non-English) hashtags.
/#[_a-zA-Z0-9]{1,139}/is a regex that will match common hashtags per the #Limitations documented above, while liberally allowing numbers-only and numbers-starting hashtags, limited to hashtags that will fit on Twitter./#\w{1,139}/is shorter.