Close the two XSD-regex gaps from the audit:
- \p{...} and \P{...} now resolve Unicode general categories (one-letter
groups like \p{L} and two-letter codes like \p{Lu}/\p{Nd}) through
Swift's own scalar generalCategory, so no character tables are vendored.
A curated set of well-known \p{Is<Block>} blocks is supported; an
unknown category or block name is a compile error rather than a guess.
- Character-class subtraction [a-z-[aeiou]] removes the subtrahend from a
class, and nests ([a-z-[b-d-[c]]]) and composes with categories.
Categories and subtraction work both as standalone atoms and inside
character classes, so XSD pattern facets that use them now validate.
Closes#89
Use let for never-mutated bindings in DateTimeParser, HTMLEntities, and the
XSLT parser, and drop the redundant Unicode.Scalar Comparable conformance
that the standard library already provides. No behavior change.
Add the PureXML.Regex namespace: a recursive-descent parser for the XSD
regex grammar (literals, ., character classes with ranges and negation, the
\d \w \s family and negations, single-char escapes, grouping, alternation,
and the ?, *, +, {n}, {n,}, {n,m} quantifiers) compiled to a Thompson NFA.
matches(_:) is whole-string as xs:pattern requires, and runs linear in the
input with no backtracking blow-up. \p{...} category escapes are not yet
supported.
Closes#59Closes#60Closes#30
