OrderedValue.== compared doubles with IEEE equality (NaN != NaN), so a NaN value never matched a NaN enumeration member and was rejected: <v>NaN</v> against xs:double restricted by <xs:enumeration value="NaN"/> is valid, and PureXML rejected it (a cardinal-rule false positive). NaN is now treated as identical to itself in value-space equality, the identity the reference (libxml2) and XSD 1.1 use throughout; an adversarial critic flagged the shared comparison (also used by key/unique and fixed), so the key/fixed behaviour was verified against xmllint: libxml2 collides two NaN unique keys and matches fixed="NaN", i.e. the same identity, so one identity == matches the reference everywhere. Ordering (<) keeps NaN incomparable, so range facets are unaffected. Found by a new generated-value facet differential (FacetValidationDifferentialTests, opt-in via FACET_DIFF) over ~10000 datatype/facet values: one FP found, zero after; the four W3C XSTS buckets held, full suite passes, SchemaDoubleEnumerationTests locks all three relations.
xs:unique/xs:key/xs:keyref were quadratic over a wide list of targets.
The duplicate check compared each value tuple against every tuple already
seen (and a keyref against every referenced key), and the error-location
helper rescanned the parent's whole child list to position each target.
Key tuples in a Set by their raw string when field equality provably
reduces to a raw string comparison (whitespace-preserving lexical types,
no colon, which is most ids); value-space types (numeric, boolean, date),
whitespace-collapsing types, and QName-bearing values keep the exact
pairwise comparison, so which documents pass is unchanged. Position each
target through a per-parent, per-name index built once.
A 16000-item xs:unique document drops from about 4.0 s to about 0.12 s
(~34x), and the cost is now linear. The full local suite and the W3C
XSTS datatype/identity conformance corpus are unchanged.
Add the PureXML.Schema namespace validating XSD Part 2 built-in datatypes
and constraining facets. Built-ins span string/boolean/decimal, the bounded
integer family with intrinsic bounds, float/double, duration, the eight
date/time types, hexBinary, base64Binary, anyURI, QName, and the
Name/NCName/NMTOKEN/language family. Facets: length/minLength/maxLength,
pattern (via the regex engine), enumeration (value-space comparison),
whiteSpace, min/maxInclusive/Exclusive, totalDigits, fractionDigits.
Decimals compare exactly with no floating-point loss; date/time fields are
range-validated with leap years, 24:00:00, and timezone bounds.
Closes#8