parse

Parses an expression in the subset of JSONPath the engine uses:

$                    the document
$.user.name          a field of a field
$.items[0]           an array element
$["odd name"]        a field whose name is not a bare identifier

Deliberately not full JSONPath. Wildcards, slices and filters are query concerns; a path here identifies exactly one location, which is what makes it usable as an index key.

A field name that is not [A-Za-z0-9_]+ requires the bracket form, and $["odd name"] above understates how ordinary that is. $.@type does not parse — the dot form takes an identifier — so in a protobuf-JSON corpus, where @type is on every message, the bracket form is not an edge case but the rule. In Kotlin the readable spelling is a raw string: VariantPath.parse("""$["@type"]""").

Inside the quotes a backslash escapes the next character literally, so $["a\nb"] is the three-character name anb and not a, newline, b; a real newline in a name is written raw and round-trips. Self-consistent, and deliberately not RFC 9535 §2.7's escaping — toNormalizedPath and parseNormalized are that grammar, and they are the pair to reach for when the path is going somewhere outside the engine.

Throws