Hwaro::Core::Build::SummaryReaders
Can a template set print a page's automatic excerpt?
The excerpt is a second markdown render of every page, so ParseContent
only builds it when something can print it (auto_summary_read?). A
template prints it by naming summary (page.summary, p.summary,
page_summary, summary_truncated) — or by printing a whole page object,
whose summary key then comes along unnamed: {{ p }}, {{ p | tojson }},
{{ section.pages }}, {% for k, v in page %}, p[field], or a page
handed to a macro that does any of that.
This is a static, text-level over-approximation, like TemplateVarFeatures:
anything it cannot classify counts as a reader. A false "reader" only costs
the excerpt render; a false "no reader" would blank summary in the
output, so every rule below errs toward reading.
Constants
Serialization, dict iteration and field names held in variables print fields nobody named.
What may follow a page value without printing it: a field access, a
literal-key subscript, a count, a test or a boolean/comparison operator.
The end of the expression is NOT harmless: {{ p }} prints the page.
Functions returning page-carrying objects.
Top-level template variables that are, or contain, page objects (the
HTML strings pagination / section_list and the term name
taxonomy_term are not).
Attributes whose value is a page, a section, a term, an author or a list of them.