Mihaela Mihaljevic
1ae6680d94
Add PureXML.XPath: a compiled location-path query engine reimplemented from the XPath 1.0 specification; no upstream code copied. - Compiler parses a path into steps; Evaluator walks the tree returning a Selection node-set (node or attribute) in document order. - Forward axes only (child, descendant //, self ., attribute @), since the value model has no parent pointers. Node tests: name, *, text(), node(), comment(). Predicates: [n], [@a], [@a='v'], [child], [child='v']. - Public surface: XPath.Query (init compiles, evaluate/elements/strings), the Selection enum (element / stringValue), QueryError, and the one-shot PureXML.xpath(_:over:). Upward/sibling axes and the full expression language are explicitly out of scope. - 12 XPath tests; 61 total.
16 lines
579 B
Swift
16 lines
579 B
Swift
extension PureXML.XPath {
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/// The supported XPath axes. The model is a value tree without parent
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/// pointers, so only the forward axes are available; upward axes (parent,
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/// ancestor) and sibling axes are intentionally out of scope.
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enum Axis: Equatable {
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/// Immediate children (the default axis).
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case child
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/// All descendants at any depth (reached with `//`).
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case descendant
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/// The context node itself (`.`).
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case selfNode
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/// Attributes of the context element (`@`).
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case attribute
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}
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}
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