krastanov/julia-toml

Julia TOML

Use TOML stdlib APIs to parse TOML safely and serialize Julia data back to TOML.

Parse TOML

Use throwing APIs when malformed TOML should fail fast:

using TOML
cfg = TOML.parse(text)
cfg2 = TOML.parsefile("config.toml")

Use non-throwing APIs when parse errors should be handled explicitly:

res = TOML.tryparse(text)
if res isa TOML.ParserError
    # handle parser error
end

For high-volume parsing of many small TOML files, reuse TOML.Parser() to reduce allocations.

Handle Parse Errors

TOML.ParserError includes useful fields for diagnostics:

• pos for failing byte position.
• table for partially parsed data.
• type for parser error category.

When errors need user-facing feedback, report file path + position + nearby source.

Write TOML

Use TOML.print for serialization:

TOML.print(io, data)

Control key ordering when needed:

TOML.print(io, data; sorted=true, by=length)

For custom structs, pass to_toml converter that maps unsupported values to supported TOML types.

Type Constraints to Remember

TOML.print supports values that map to TOML primitives/tables, including dict-like tables, integers/floats, booleans, and Dates.Date, Dates.Time, Dates.DateTime (subject to TOML stdlib conversion constraints).

Reference

• references/toml-api-patterns.md - parse/tryparse/print API behavior and examples

Related Skills

• julia-package-dev - package workflows using TOML files
• julia-yaml - analogous workflow for YAML serialization