3.5 Other metadata languages #

YAML also has the same tradeoff as Markdown: human readability over a strict specifi- cation. This tradeoff comes with complexities in parsers and weird edge cases that might not be easy to understand. We have chosen YAML in this book for the configuration file due to its popularity and ease of readability. Hugo supports TOML and JSON as other metadata languages apart from YAML. Appendix B goes over TOML and JSON in detail, and table 3.2 provides a quick comparison of their features.

Table 3.2 Metadata language comparison

• TOML (Tom’s Obvious Minimal Language) has the objective of ensuring that there is one standard way of writing a particular data item. YAML’s automatic guess- ing of data types makes it easier to read but can lead to cases where YAML infers a wrong type. For example, plain text is a string, but if the plain text is the word true, it becomes a Boolean. TOML avoids that confusion with a strongly defined system where we have to enclose every string in quotes.
• JSON (JavaScript Object Notation) is a popular format for exchanging information and is much easier than YAML and TOML for generation and machine parsing. The most significant advantage of JSON is the availability of high-performance parsers in most programming languages and familiarity with this format among developers. Graphical editors and CMS solutions typically use JSON for Hugo interaction.

NOTE You will find a lot of resources from the Hugo community in the TOML format. TOML is more straightforward to copy and paste due to its nonstrict spacing policy. If you happen to write a parser, TOML will be much easier to parse. For an advanced Hugo user, TOML is an excellent language to know.