projectfluent
Is there an XML version?
Not exactly. FTL text files are the canonical data format.
There are a number of different Fluent implementations. The FTL files that go in and what translations they spit out should be 100% compatible (if they are doing everything right), but how they get there differs somewhat between implementations. Most of them parse the FTL format into some intermediate representation –usually an AST in whatever in-memory format is native to the language– that is used internally. Many languages have facilities that can dump such an AST representation to JSON, XML, or the like. Many of them even use the JSON form of the parsed data for tests. It would be trivial in most language implementations to also allow a direct read of those AST dumps back into the host language. I don't know of any that actually do that, but you could easily implement it yourself.
It's also possible to keep FTL data it a database ... or XML if you like, and simply write a data retrieval layer that feeds content in FTL format to the Fluent implementation no matter what format it was stored in on the backend.
