Support biblatex field ids for citekey aliases

[nichtich]

The biblatex manual defines field "ids" as comma separated list of citation key aliases for the main citation key. pandoc-citeproc seems to just ignore this field. Instead it should allow to use alias ids for citation:

@book{foo,
  author = {Alice},
  year = {2042},
  ids = {bar, doz}
}

Then reference book foo in Markdown:

@bar

[jgm]

Only way to do this would be to create several references that are identical except for the id. We could do that, though.

[njbart]

Only way to do this would be to create several references that are identical except for the id.

I’m afraid this won’t work without further modifications. As it is, pandoc-citeproc creates two reference section entries in such cases, and disambiguates these. I’m not sure whether there are other workable solutions: Checking whether biblio database entries are identical (except for the citekey) would of course work in principle, but I have no idea what that would mean performance-wise. Other solutions might be to allow a field called other-ids or similar. (Arguably, this wouldn’t even infract upon the CSL specs, since the commonly used id field isn’t defined there either …)

(The reason I’m interested: zotxt allows users to define additional citekeys for an entry by adding these to a tag or a note – but if more than one citekey per entry is used in a pandoc document, the entry is duplicated in the references section as well. An easy workaround is to avoid using different citekeys for the same entry, but a more foolproof approach, if possible at all, would of course be welcome.)

MWE:

pandoc -s -F pandoc-citeproc -t plain << EOT

Snow is white [@item1, 1]. Water is wet [@item2, 2].

# References {-}

---
references:
- id: item1
  type: book
  author:
  - family: Doe
    given: Jane
  issued:
    - year: 2018
  title: A title
- id: item2
  type: book
  author:
  - family: Doe
    given: Jane
  issued:
    - year: 2018
  title: A title
...
EOT

Actual output:

Snow is white (Doe 2018a, 1). Water is wet (Doe 2018b, 2).

REFERENCES

Doe, Jane. 2018a. _A Title_.

———. 2018b. _A Title_.

Expected:

Snow is white (Doe 2018, 1). Water is wet (Doe 2018, 2).

REFERENCES

Doe, Jane. 2018. _A Title_.

[jgm]

Yes, actually, I think we could introduce an other-ids field. This would require:

• changes in References module to add the field
• changes in the Bibtex parser to populate the field
• change getReference in References to also check the other ids

Not sure if that would suffice by itself, but it would be a start.