A <value> pattern now carries its datatype, so matching compares the
instance and the literal in that type's value space rather than purely
lexically. Numeric and date/time types compare by value (1 equals 01,
1.5 equals 1.50); booleans treat 1/true and 0/false as equal; string and
token compare by their whitespace-normalized lexical form, as before.
Untyped values default to the built-in token type, and a bare string
literal in the compact syntax is token-typed. Durations and binary types
fall under the lexical rule.
