Runtime expression `name` rule inconsistent with path template grammar

The runtime expression ABNF grammar defines:

name = *( char )
token = 1*tchar

The * (zero or more) quantifier on name means expressions like $request.query. and $request.path. with empty names are syntactically valid per the grammar.

The OpenAPI spec states that the Parameter Object's name field is REQUIRED:

REQUIRED. The name of the parameter. Parameter names are case-sensitive.

A required field with an empty string value is arguably not meaningful, though the spec doesn't explicitly say "non-empty".

For path parameters specifically, this is inconsistent with the path template grammar introduced in OpenAPI 3.2.0:

template-expression-param-name = 1*( %x00-7A / %x7C / %x7E-10FFFF )

The 1* quantifier requires at least one character for path parameter names. So {userId} is valid but {} is not. Yet the runtime expression $request.path. (empty name) is accepted by the grammar.

For query parameters, the situation is less clear — HTTP technically allows empty query parameter keys (?=value), though this is extremely uncommon.

For consistency with the path template grammar and the token = 1*tchar rule (which already requires at least one character for headers), consider changing:

name = *( char )

to:

name = 1*( char )

This would require at least one character for query and path parameter names, aligning the runtime expression grammar with the path template grammar.

Leggi le regole ABNF dell’espressione runtime per name e token insieme alla grammatica dei template dei percorsi di OpenAPI 3.2. Determina se i nomi di query vuoti sono previsti prima di decidere se name debba richiedere un carattere; il lavoro è completato quando la grammatica e il testo circostante della specifica documentano coerentemente la decisione.