Getting a owned IriRef<MownStr>> from a SimpleTerm

[GordianDziwis]

I am currently converting my codebase to sophia 0.8.0. And I have some ugliness I want to get rid of. In the Some(dt_inner) match arm, I need an owned IriRef<MownStr>> from a SimpleTerm, which gets complicated because iri() takes a reference to self of simple_term which goes out of scope after the closure.

My workaround is:

                let dt = match datatype.as_ref() {
                    Some(dt_inner) => dt_inner.try_as_term(diagram).map(
                        |simple_term: SimpleTerm| {
                            IriRef::new_unchecked(
                                simple_term.iri().unwrap().to_string().into(),
                            )
                        },
                    )?,
                    None => xsd::string.iri().unwrap(),
                };
                SimpleTerm::LiteralDatatype(lexical_form.as_str().into(), dt)

Is there a nicer way to do this?

[pchampin]

You could remove some ugliness by using IriRef::map_unchecked.

        let dt = match datatype.as_ref() {
            Some(dt_inner) => dt_inner
                .try_as_term(diagram)?
                .iri()
                .unwrap()
                .map_unchecked(|txt| txt.to_string().into()),
            None => xsd::string.iri().unwrap(),
        };
        SimpleTerm::LiteralDatatype(lexical_form.as_str().into(), dt)

Assuming you have control over the type of dt_inner, you might also add a dedicated method to it (which would do exactly what is above), allowing you to write:

        let dt = match datatype.as_ref() {
            Some(dt_inner) => dt_inner.try_as_iri(diagram)?,
            None => xsd::string.iri().unwrap(),
        };
        SimpleTerm::LiteralDatatype(lexical_form.as_str().into(), dt)

where the return type of try_as_iri(diagram) is IriRef<MownStr<'static>>.

NB: if you don't have control over the type of dt_inner, you could still add the try_as_iri method via an extension trait.