I see a lot of potential in this, and already see some use-cases. Unfortunately I don’t have the bandwith, nor the full skills to make this happens. So I am just writing this in the hope that the idea is implemented by someone, or that someone tells me it is totally nonsense…

Here are the semantic annotations use-cases I see with such a Semantic Markdown :

1. Annotate a span or title that corresponds to an entity ;
2. Annotate a piece of text with an existing URI for an entity;
3. Create some statements on an entity;

Note that I am not necessarily looking for a way to produce RDFa annotations on the generated HTML, although that would be nice for a schema.org use-case. Any conversion route from the original semantically annotated markdown to a set of triples would be fine.

My source of inspiration is essentially Span Inline Attribute Lists » from the Kramdown syntax.

Annotate a span that corresponds to an entity

This piece of Semantic Markdown :

Tomorrow I am travelling to _Berlin_ {.schema:Place}

When interprered by a Semantic Markdown parser would produce this set of triples :

_:1 a <http://schema.org/Place> .
_:1 rdfs:label “Berlin” .

The span immediately preceding the « {.xxxx} » annotation is taken as the label of the entity. The use of rdfs:label to store the label of the entity could be subject to a parser configuration option.

One could imagine that a semantic markdown parser relies on the same RDFa Initial Context to interpret the « schema: » prefix without further declaration. But what about other ontologies ? we would need some kind of prefixes / vocab declaration somewhere in the document, just like in RDFa.

Note also that Markdown parser supporting the « {.xxxxx} » syntax will also insert this value as a CSS class on the corresponding span, so we win both on the CSS level and the semantic level.

Annotate a title

Similarly, we could annotate a title

### European Semantic Web Conference {.schema:Event}
Lorem ipsum...

In that case, the full content of the title is interpreted as the label of the entity :

_:1 a <http://schema.org/Event> .
_:1 rdfs:label “European Semantic Web Conference” .

Annotate with a known URI

Tomorrow I am travelling to [Berlin](https://www.wikidata.org/wiki/Q64) {.schema:Place}

Would yield

<https://www.wikidata.org/wiki/Q64> a <http://schema.org/Place> .
<https://www.wikidata.org/wiki/Q64> rdfs:label “Berlin” .

Describe an entity

If a list follows an annotated entity, then it should be interpreted as a set of predicates with this entity as subject :

### Specifications Meeting {.schema:Event}

* Date : _11/10_{.schema:startDate}
* Place {.schema:location} : Our office, Street name, 75014 Paris
* Meeting participants : 
  {.schema:attendee}
  * Thomas Francart{.schema:Person}
  * [Someone else](https://www.wikidata.org/wiki/Q80)
  * Tim Foo
* Description : Some information not annotated

### titre suivant
Lorem ipsum...

Should yield :

_:1 a <http://schema.org/Event> .
_:1 rdfs:label “Specifications Meeting” .
_:1 <http://schema.org/startDate> "11/10" .
_:1 <http://schema.org/location> "Our office, Street name, 75014 Paris" .
_:1 <http://schema.org/attendee> _:2 , <https://www.wikidata.org/wiki/Q80>, _:3 .

# attendee that is annotated : we know a type and a name
_:2 a <http://schema.org/Person>
_:2 rdfs:label “Thomas Francart” .

# attendee that is annotated with a URI : we keep the URI and add a label to it (?)
<https://www.wikidata.org/wiki/Q80> rdfs:label "Someone else" .

# attendee that is not annotated - but we know he was an attendee
_:3 rdfs:label "Tim Foo" .

1. If a list follows a title or a paragraph that contains an annotated entity…
2. Then items in this list correspond to a property of this entity…
3. And can be annotated with a property
4. The property annotation can be placed on an inline text, or right before or after a `:` or `=` character
5. If the property annotation immediatly precedes a list, then all items in this list would be considered values for that property, and in that case could be either : entities annotated with a type, or entities identified by a URI, or entites not annotated (and in that case we would consider them as blank nodes with only a label

Related works

Metadata for Markdown, a Python extension to generated JSON-LD from YAML section in a Markdown document.

EDIT : PanDoc divs and spans : https://pandoc.org/MANUAL.html#divs-and-spans

I like the <span> syntax :

[This is *some text*]{.class key="val"}

This is close ! but still would not produce triples, unless one writes explicitely RDFa :

My name is [Thomas Francart]{typeof="schema:Person"}

Cet article Semantic Markdown Specifications est apparu en premier sur Sparna Blog.