VariantPath

A location inside a document, as a list of steps from the root.

Paths are the unit everything above this module names data by: the catalog counts observations per path, an index is built for a path, and a query predicate applies to a path. Keeping them as a parsed list of steps rather than as a string means that comparison, prefixing and grouping are exact rather than textual — $["a.b"] and $.a.b are different locations and must never compare equal.

PATHS.md compares this grammar with the other three, which is where to look before handing one expression to two of them: parse reads " and a backslash literally, §2.7 reads ' and seven escapes, and RFC 9535 reads both quotings and its own escapes. parseJsonPathOrNull is the reader for an expression that came from outside the engine, and the one to reach for instead of comparing parse(e).toString() with e.