* date
- Specifies the creation date of the page. The date can be entered in
- nearly any format, since it's parsed by [[!cpan TimeDate]].
+ Specifies the creation date of the page. This creates a
+ `<meta name="date" content="...">` header in the HTML output, but also
+ modifies the internal `ctime` in the
+ [[!iki tips/inside_dot_ikiwiki desc="internal index"]].
+ The date can be entered in nearly any format, since it's parsed by
+ [[!cpan TimeDate]] but invalid dates yield an error in 3.20180321
+ or later.
* stylesheet
modification time, like Planet: for instance, when editing an old blog post
to add tags, you could set `updated` to be one second later than the original
value. The date/time can be given in any format that
- [[!cpan TimeDate]] can understand, just like the `date` field.
+ [[!cpan TimeDate]] can understand, just like the `date` field and maps to the
+ `<meta name="updated" content="...">` HTML header and internal `mtime` field.
* foaf
If the field is not one of the above predefined fields, the metadata will be
written to the generated html page as a <meta> header. For example,
-`\[[!meta foo="bar"]]` becomes `<meta name="foo" content="bar">`. As with `name`, this
-won't be allowed if the [[!iki plugins/htmlscrubber desc=htmlscrubber]] plugin is enabled.
+`\[[!meta foo="bar"]]` becomes `<meta name="foo" content="bar">`. As
+with `name`, this won't be allowed if the [[!iki plugins/htmlscrubber
+desc=htmlscrubber]] plugin is enabled.
+
+This syntax cannot be used for meta headers with unusual names, in
+particular names containing `:` such as `flattr:id` and `twitter:card`.
+Please use `\[[!meta name="..." content="..."]]` for those headers.
[[!meta robots="noindex, follow"]]