pub fn value_equality_key(v: &Value) -> Option<String>Expand description
A canonical key for value-equality grouping/distinct (XSLT 2.0
§14.3 group-by uses the eq operator). Returns Some only for
the typed values whose eq semantics differ from their lexical
string: temporal values normalise to a UTC instant (so two
dateTimes in different time zones for the same instant share a
key), durations to their total magnitude. None for everything
else — the caller uses the string-value, which already matches
eq for strings / numbers / booleans.