Data Formats

Rootbeer ships built-in codecs for the configuration formats you actually encounter in dotfiles. Every codec is a sub-table on rb with the same four-function shape:

rb.<fmt>.encode(t)        -- table  → string
rb.<fmt>.decode(s)        -- string → table
rb.<fmt>.read(path)       -- path   → table   (slurp ∘ decode)
rb.<fmt>.write(path, t)   -- path, table → () (encode ∘ file)

encode and decode are pure transformations. read slurps a file synchronously at plan time — the file must exist when your script runs. write is deferred: it appends a WriteFile op that runs during rb apply, exactly like rb.file(). A trailing newline is always added on write so the output is well-formed.

Available codecs

Codec	Read	Write	Notes
json	✓	✓	Pretty-printed with 2-space indent.
toml	✓	✓	Datetimes decode as strings.
yaml	✓	✓	Tags decode transparently to scalars.
plist	✓	✓	XML output; decode accepts XML or binary.

Encoding rules

These apply to every codec. Format-specific behaviour is documented on each codec's page.

• Tables with consecutive integer keys starting at 1 become arrays / sequences. All other tables become objects / maps / dictionaries.
• nil values are omitted from the output.
• NaN and Infinity are rejected by formats that cannot represent them (JSON, plist).
• Lua functions, threads, and userdata error on encode — they have no serialized form.

Choosing format by extension

Three writes, one config table:

local data = { theme = "dark", recent = { "a.txt" } }

rb.yaml.write("~/.config/app/config.yaml", data)
rb.json.write("~/.config/app/config.json", data)
rb.toml.write("~/.config/app/config.toml", data)