Close the remaining documented parity edges:
- Canonical XML 2.0 TrimTextNodes: an option that strips leading and trailing
whitespace from each text node (dropping all-whitespace nodes), exposed as
Options.canonical2.
- XML Catalog delegation and chaining: delegatePublic, delegateSystem,
delegateURI, and nextCatalog entries are parsed, and resolveSystem/
resolvePublic/resolveURI gain a loadingCatalog overload that follows the
longest matching delegate prefix and then each nextCatalog, with a
visited-set guard against cycles.
- XPath number formatting: the canonical string form now expands any exponent
in the shortest double rendering to a plain decimal, since XPath 1.0 forbids
scientific notation.
Closes#70
Compile and evaluate full XPath 1.0 expressions, not just location paths.
Add the four-type Value (node-set, boolean, number, string) with the spec's
coercion rules and canonical number formatting, a recursive-descent parser
for the operator grammar (or/and, equality, relational, additive,
multiplicative, unary minus, union) whose grammatical position disambiguates
* and the operator keywords, function calls, variable references, and filter
expressions. Predicates are now arbitrary expressions (a numeric predicate
is a position test). Comparison follows the node-set quantification rules.
Query gains value/number/string/boolean accessors and a $variable binding
map; the core functions last, position, count, not, true, false, boolean,
number, and string ship with it.
Closes#42
