xml_structure_tree

Defined in header: <orcus/xml_structure_tree.hpp>

class xml_structure_tree

Tree representing the structure of elements in XML content. Recurring elements under the same parent are represented by a single element instance. This tree only includes elements; no attributes and content nodes appear in this tree.

Public Types

enum class callback_type : uint8_t

Location of a callback function.

Values:

enumerator unknown: Location not specified or unknown.

enumerator on_repeat_node: Callback function is called when a repeated element is encountered. The argument passed to the callback function contains the name of the repeated element and its type is entity_name.

using callback_handler_type = std::function<void(std::any)>: Callback function type. It must take one argument. What value is assigned and what the type of a value is depends on the location of the callback. Refer to callback_type for details.

using range_handler_type = std::function<void(xml_table_range_t&&)>

typedef std::vector<entity_name> entity_names_type

Public Functions

xml_structure_tree() = delete

xml_structure_tree(const xml_structure_tree&) = delete

xml_structure_tree &operator=(const xml_structure_tree&) = delete

xml_structure_tree(xmlns_context &xmlns_cxt)

xml_structure_tree(xml_structure_tree &&other)

~xml_structure_tree()

void set_callback(callback_type type, callback_handler_type callback)

Assign a user-defined callback function in a specified point of execution during parsing.

Parameters:

type – Location where the callback function will be called.
callback – Callback function.

void parse(std::string_view s)

void dump_compact(std::ostream &os) const

walker get_walker() const

void process_ranges(range_handler_type rh) const

void swap(xml_structure_tree &other)

struct element

Public Functions

element()

element(const entity_name &_name, bool _repeat, bool _has_content)

Public Members

entity_name name

bool repeat

bool has_content

struct entity_name

Public Functions

entity_name()

entity_name(xmlns_id_t _ns, std::string_view _name)

bool operator==(const entity_name &r) const

std::strong_ordering operator<=>(const entity_name &r) const

Public Members

xmlns_id_t ns

std::string_view name

struct hash

Public Functions

size_t operator()(const entity_name &val) const

class walker

This class allows client to traverse the tree.

Public Functions

walker() = delete

walker(const walker &r)

~walker()

walker &operator=(const walker &r)

element root()

Set current position to the root element, and return the root element.

Returns:: root element.

element descend(const entity_name &name)

Descend into a specified child element.

Parameters:: name – name of a child element.
Throws:: general_error – if no child elements exist for the specified name.
Returns:: child element

element ascend(): Move up to the parent element.

element move_to(const std::string &path)

Move to the element specified by a path expression. The path expression may be generated by xml_structure_tree::walker::get_path.

Parameters:: path – a simple XPath like expression
Returns:: element pointed to by the path.

entity_names_type get_children()

Get a list of names of all child elements at the current element position. The list of names is in order of appearance.

Returns:: list of child element names in order of appearance.

entity_names_type get_attributes()

Get a list of names of all attributes that belong to current element. The list of names is in order of appearance.

Returns:: list of attribute names in order of appearance.

size_t get_xmlns_index(xmlns_id_t ns) const

Get a numerical, 0-based index of given XML namespace.

Parameters:: ns – XML namespace ID.
Returns:: numeric, 0-based index of XML namespace if found, or xml_structure_tree::walker::index_not_found if the namespace is not found in this structure.

std::string get_xmlns_short_name(xmlns_id_t ns) const

std::string to_string(const entity_name &name) const

Convert an entity name to its proper string representation.

Parameters:: name – entity name to convert to string.
Returns:: string representation of the entity name, including the namespace.

std::string get_path() const: Get a XPath like ID for the element inside of the XML tree.