Documentation on adding new output formats?

[evelant]

yaml, toml, and json cover a lot of use cases but not all of them. How do you go about adding a custom export format? I may have missed it but I didn't see anything about it in the docs. There are many configuration formats out there beyond yaml/toml/json. Being able to output to esoteric or arbitrary formats would likely be very useful.

[jneem]

Exporting is implemented using serde; the export function is here. If you're talking about contributing extra formats to nickel itself, you'll want to extend the ExportFormat enum and add the serialization at the place I linked to above.

If you're talking about formats that are too niche to be worth supporting upstream, and your formats have serde support, then you'll want to imitate what the export cli command does: evaluate a program, and then serialize the resulting RichTerm using serde.

Another option, of course, is to use json as an intermediate representation.