Initial project import

tools/v/vlib/encoding/xml/query.v

@@ -0,0 +1,96 @@
+module xml
+
+// get_element_by_id returns the first element with the given id, or none if no
+// such element exists in the subtree rooted at this node.
+pub fn (node XMLNode) get_element_by_id(id string) ?XMLNode {
+	// Is this the node we're looking for?
+	if attribute_id := node.attributes['id'] {
+		if attribute_id == id {
+			return node
+		}
+	}
+
+	if node.children.len == 0 {
+		return none
+	}
+
+	// Recurse into children
+	for child in node.children {
+		match child {
+			XMLNode {
+				if result := child.get_element_by_id(id) {
+					return result
+				}
+			}
+			else {}
+		}
+	}
+
+	return none
+}
+
+// get_elements_by_tag returns all elements with the given tag name in the subtree
+// rooted at this node. If there are no such elements, an empty array is returned.
+pub fn (node XMLNode) get_elements_by_tag(tag string) []XMLNode {
+	mut result := []XMLNode{}
+
+	if node.name == tag {
+		result << node
+	}
+
+	if node.children.len == 0 {
+		return result
+	}
+
+	// Recurse into children
+	for child in node.children {
+		if child is XMLNode {
+			result << child.get_elements_by_tag(tag)
+		}
+	}
+
+	return result
+}
+
+// get_elements_by_attribute returns all elements with the given attribute-value pair in
+// the subtree rooted at this node. If there are no such elements, an empty array is returned.
+pub fn (node XMLNode) get_elements_by_attribute(attribute string, value string) []XMLNode {
+	mut result := []XMLNode{}
+
+	if attribute_value := node.attributes[attribute] {
+		if attribute_value == value {
+			result << node
+		}
+	}
+
+	if node.children.len == 0 {
+		return result
+	}
+
+	// Recurse into children
+	for child in node.children {
+		if child is XMLNode {
+			result << child.get_elements_by_attribute(attribute, value)
+		}
+	}
+
+	return result
+}
+
+// get_element_by_id returns the first element with the given id, or none if no
+// such element exists.
+pub fn (doc XMLDocument) get_element_by_id(id string) ?XMLNode {
+	return doc.root.get_element_by_id(id)
+}
+
+// get_elements_by_attribute returns all elements with the given attribute-value pair.
+// If there are no such elements, an empty array is returned.
+pub fn (doc XMLDocument) get_elements_by_attribute(attribute string, value string) []XMLNode {
+	return doc.root.get_elements_by_attribute(attribute, value)
+}
+
+// get_elements_by_tag returns all elements with the given tag name.
+// If there are no such elements, an empty array is returned.
+pub fn (doc XMLDocument) get_elements_by_tag(tag string) []XMLNode {
+	return doc.root.get_elements_by_tag(tag)
+}