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# element

## `xsdata.formats.dataclass.parsers.nodes.element`

### `ElementNode`

Bases: `XmlNode`

XmlNode for complex elements.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`meta` | `XmlMeta` | The class binding metadata instance | required
`attrs` | `dict` | The element attributes | required
`ns_map` | `dict` | The element namespace prefix-URI map | required
`config` | `ParserConfig` | The parser config instance | required
`context` | `XmlContext` | The models context instance | required
`position` | `int` | The current objects length, everything after this position are considered children of this node. | required
`mixed` | `bool` | Specifies whether this node supports mixed content. | `False`
`derived_factory` | `type | None` | Derived element factory | `None`
`xsi_type` | `str | None` | The xml type substitution | `None`
`xsi_nil` | `bool | None` | Specifies whether element has the xsi:nil attribute | `None`

Attributes:

Name | Type | Description
--- | --- | ---
`assigned` | `set[int]` | A set to store the processed sub-nodes
`tail_processed` | `bool` | Whether the tail process is consumed

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    class ElementNode(XmlNode):
        """XmlNode for complex elements.

        Args:
            meta: The class binding metadata instance
            attrs: The element attributes
            ns_map: The element namespace prefix-URI map
            config: The parser config instance
            context: The models context instance
            position: The current objects length, everything after
                this position are considered children of this node.
            mixed: Specifies whether this node supports mixed content.
            derived_factory: Derived element factory
            xsi_type: The xml type substitution
            xsi_nil: Specifies whether element has the xsi:nil attribute

        Attributes:
            assigned: A set to store the processed sub-nodes
            tail_processed: Whether the tail process is consumed
        """

        __slots__ = (
            "assigned",
            "attrs",
            "config",
            "context",
            "derived_factory",
            "meta",
            "mixed",
            "ns_map",
            "position",
            "tail_processed",
            "xsi_nil",
            "xsi_type",
        )

        def __init__(
            self,
            meta: XmlMeta,
            attrs: dict,
            ns_map: dict,
            config: ParserConfig,
            context: XmlContext,
            position: int,
            mixed: bool = False,
            derived_factory: type | None = None,
            xsi_type: str | None = None,
            xsi_nil: bool | None = None,
        ):
            """Initialize the xml node."""
            self.meta = meta
            self.attrs = attrs
            self.ns_map = ns_map
            self.config = config
            self.context = context
            self.position = position
            self.mixed = mixed
            self.derived_factory = derived_factory
            self.xsi_type = xsi_type
            self.xsi_nil = xsi_nil
            self.assigned: set[int] = set()
            self.tail_processed: bool = False

        def bind(
            self,
            qname: str,
            text: str | None,
            tail: str | None,
            objects: list[Any],
        ) -> bool:
            """Bind the parsed data into an object for the ending element.

            This entry point is called when a xml element ends and is
            responsible to parse the current element attributes/text, bind
            any children objects and initialize new object.

            Args:
                qname: The element qualified name
                text: The element text content
                tail: The element tail content
                objects: The list of intermediate parsed objects

            Returns:
                Whether the binding process was successful or not.
            """
            obj: Any = None
            if not self.xsi_nil or self.meta.nillable:
                params: dict = {}
                self.bind_attrs(params)
                self.bind_content(params, text, tail, objects)
                obj = self.config.class_factory(self.meta.clazz, params)

            if self.derived_factory:
                obj = self.derived_factory(qname=qname, value=obj, type=self.xsi_type)

            objects.append((qname, obj))

            if not self.tail_processed:
                tail = ParserUtils.normalize_content(tail)
                if tail:
                    objects.append((None, tail))

            return True

        def bind_content(
            self,
            params: dict,
            text: str | None,
            tail: str | None,
            objects: list[Any],
        ) -> None:
            """Parse the text and tail content.

            Args:
                params: The class parameters
                text: The element text content
                tail: The element tail content
                objects: The list of intermediate parsed objects
            """
            wild_var = self.meta.find_any_wildcard()
            if wild_var and wild_var.mixed:
                self.bind_mixed_objects(params, wild_var, objects)
                bind_text = False
            else:
                self.bind_objects(params, objects)
                bind_text = self.bind_text(params, text)

            if not bind_text and wild_var:
                self.bind_wild_text(params, wild_var, text, tail)

            for key in params:
                if isinstance(params[key], PendingCollection):
                    params[key] = params[key].evaluate()

        def bind_attrs(self, params: dict[str, Any]) -> None:
            """Parse the element attributes.

            Scenarios:
                - Each attribute matches a class field
                - Class has a wildcard field that sucks everything else

            Args:
                params: The class parameters

            Raises:
                ParserError: If the document contains an unknown attribute
                    and the configuration is strict.
            """
            if not self.attrs:
                return

            for qname, value in self.attrs.items():
                var = self.meta.find_attribute(qname)
                if var and var.name not in params:
                    self.bind_attr(params, var, value)
                else:
                    var = self.meta.find_any_attributes(qname)
                    if var:
                        self.bind_any_attr(params, var, qname, value)
                    else:
                        if (
                            self.config.fail_on_unknown_attributes
                            and target_uri(qname) != Namespace.XSI.uri
                        ):
                            raise ParserError(
                                f"Unknown attribute {self.meta.qname}:{qname}"
                            )

        def bind_attr(self, params: dict, var: XmlVar, value: Any) -> None:
            """Parse an element attribute.

            Ignores fields with init==false!

            Args:
                params: The class parameters
                var: The xml var instance
                value: The attribute value
            """
            value = ParserUtils.parse_var(
                meta=self.meta,
                var=var,
                config=self.config,
                value=value,
                ns_map=self.ns_map,
            )

            if var.init:
                params[var.name] = value
            else:
                ParserUtils.validate_fixed_value(self.meta, var, value)

        def bind_any_attr(self, params: dict, var: XmlVar, qname: str, value: Any) -> None:
            """Parse an element attribute to a wildcard field.

            Args:
                params: The class parameters
                var: The xml var instance
                qname:  The attribute namespace qualified name
                value: The attribute value
            """
            if var.name not in params:
                params[var.name] = {}

            params[var.name][qname] = ParserUtils.parse_any_attribute(value, self.ns_map)

        def bind_objects(self, params: dict, objects: list) -> None:
            """Bind children objects.

            Emit a warning if an object doesn't fit in any
            class parameters.

            Args:
                params: The class parameters
                objects: The list of intermediate parsed objects
            """
            position = self.position
            for qname, obj in objects[position:]:
                if not self.bind_object(params, qname, obj):
                    logger.warning("Unassigned parsed object %s", qname)

            del objects[position:]

        def bind_object(self, params: dict, qname: str, value: Any) -> bool:
            """Bind a child object.

            Args:
                params: The class parameters
                qname: The qualified name of the element
                value: The parsed object

            Returns:
                Whether the parsed object can fit in one of class
                parameters or not.
            """
            for var in self.meta.find_children(qname):
                if var.is_wildcard:
                    return self.bind_wild_var(params, var, qname, value)

                if self.bind_var(params, var, value):
                    return True

            return False

        @classmethod
        def bind_var(cls, params: dict, var: XmlVar, value: Any) -> bool:
            """Bind a child object to an element field.

            Args:
                params: The class parameters
                var: The matched xml var instance
                value: The parsed object

            Returns:
                Whether the parsed object can fit in one of class
                parameters or not.
            """
            if var.init:
                if var.list_element:
                    items = params.get(var.name)
                    if items is None:
                        params[var.name] = PendingCollection([value], var.factory)
                    else:
                        items.append(value)
                elif var.name not in params:
                    params[var.name] = value
                else:
                    return False

            return True

        def bind_wild_var(self, params: dict, var: XmlVar, qname: str, value: Any) -> bool:
            """Bind a child object to a wildcard field.

            The wildcard might support one or more values. If it
            supports only one the values are nested under a parent
            generic element instance.

            Args:
                params: The class parameters
                var: The wildcard var instance
                qname: The qualified name of the element
                value: The parsed value

            Returns:
                Always true, since wildcard fields can absorb any value.
            """
            value = self.prepare_generic_value(qname, value)

            if var.list_element:
                items = params.get(var.name)
                if items is None:
                    params[var.name] = PendingCollection([value], var.factory)
                else:
                    items.append(value)
            elif var.name in params:
                previous = params[var.name]
                factory = self.context.class_type.any_element

                if not isinstance(previous, factory) or previous.qname:
                    params[var.name] = factory(children=[previous])

                params[var.name].children.append(value)
            else:
                params[var.name] = value

            return True

        def bind_mixed_objects(self, params: dict, var: XmlVar, objects: list) -> None:
            """Bind children objects to a mixed content wildcard field.

            Args:
                params: The class parameters
                var: The wildcard var instance
                objects: The list of intermediate parsed objects
            """
            pos = self.position
            params[var.name] = list(starmap(self.prepare_generic_value, objects[pos:]))
            del objects[pos:]

        def prepare_generic_value(self, qname: str | None, value: Any) -> Any:
            """Wrap primitive text nodes in a generic element.

            Args:
                qname: The qualified name of the element
                value: The parsed object

            Returns:
                The original parsed value if it's a data class, or
                the wrapped primitive value in a generic element.
            """
            if qname and not self.context.class_type.is_model(value):
                any_factory = self.context.class_type.any_element
                value = any_factory(qname=qname, text=converter.serialize(value))

            return value

        def bind_text(self, params: dict, text: str | None) -> bool:
            """Bind the element text content.

            Args:
                params: The class parameters
                text: The element text content

            Returns:
                Whether the text content can fit in one of class
                parameters or not.
            """
            var = self.meta.text

            if not var or (text is None and not self.xsi_nil):
                return False

            if self.xsi_nil and not text:
                value = None
            else:
                value = ParserUtils.parse_var(
                    meta=self.meta,
                    var=var,
                    config=self.config,
                    value=text,
                    ns_map=self.ns_map,
                )

            if var.init:
                params[var.name] = value
            else:
                ParserUtils.validate_fixed_value(self.meta, var, value)

            return True

        def bind_wild_text(
            self,
            params: dict,
            var: XmlVar,
            text: str | None,
            tail: str | None,
        ) -> bool:
            """Bind the element text and tail content to a wildcard field.

            If the field is a list, prepend the text.
            Otherwise, build a generic element with the text/tail content
            and any attributes. If the field is already occupied, then this
            means the current node is a child, and we need to nested them.

            Args:
                params: The class parameters
                var: The wildcard var instance
                text: The element text content
                tail: The element text content

            Returns:
                Whether the text content can fit in one of class
                parameters or not.
            """
            text = ParserUtils.normalize_content(text)
            tail = ParserUtils.normalize_content(tail)
            if text is tail is None:
                return False

            if var.list_element:
                items = params.get(var.name)
                if items is None:
                    params[var.name] = items = PendingCollection(None, var.factory)

                items.insert(0, text)

            else:
                previous = params.get(var.name, None)
                factory = self.context.class_type.any_element
                generic = factory(
                    text=text,
                    tail=tail,
                    attributes=ParserUtils.parse_any_attributes(self.attrs, self.ns_map),
                )
                if previous:
                    generic.children.append(previous)

                params[var.name] = generic
                self.tail_processed = True

            return True

        def child(self, qname: str, attrs: dict, ns_map: dict, position: int) -> XmlNode:
            """Initialize the next child node to be queued, when an element starts.

            This entry point is responsible to create the next node type
            with all the necessary information on how to bind the incoming
            input data.

            Args:
                qname: The element qualified name
                attrs: The element attributes
                ns_map: The element namespace prefix-URI map
                position: The current length of the intermediate objects

            Raises:
                ParserError: If the child element is unknown
            """
            for var in self.meta.find_children(qname):
                unique = 0 if not var.is_element or var.list_element else var.index
                if not unique or unique not in self.assigned:
                    node = self.build_node(qname, var, attrs, ns_map, position)

                    if node:
                        if unique:
                            self.assigned.add(unique)

                        return node

            if self.config.fail_on_unknown_properties:
                raise ParserError(f"Unknown property {self.meta.qname}:{qname}")

            return nodes.SkipNode()

        def build_node(
            self,
            qname: str,
            var: XmlVar,
            attrs: dict,
            ns_map: dict,
            position: int,
        ) -> XmlNode | None:
            """Build the next child node based on the xml var instance.

            Args:
                qname: The element qualified name
                var: The xml var instance
                attrs: The element attributes
                ns_map: The element namespace prefix-URI map
                position: The current length of the intermediate objects

            Returns:
                The next child node instance, or None if nothing matched
                the starting element.
            """
            if var.is_clazz_union:
                return nodes.UnionNode(
                    meta=self.meta,
                    var=var,
                    attrs=attrs,
                    ns_map=ns_map,
                    config=self.config,
                    context=self.context,
                    position=position,
                )

            xsi_type = ParserUtils.xsi_type(attrs, ns_map)
            xsi_nil = ParserUtils.xsi_nil(attrs)
            derived_factory = self.context.class_type.derived_element

            if var.clazz:
                return self.build_element_node(
                    var.clazz,
                    False,
                    var.nillable,
                    attrs,
                    ns_map,
                    position,
                    derived_factory,
                    xsi_type,
                    xsi_nil,
                )

            if not var.any_type and not var.is_wildcard:
                return nodes.PrimitiveNode(self.meta, var, ns_map, self.config)

            datatype = DataType.from_qname(xsi_type) if xsi_type else None
            derived = var.is_wildcard
            if datatype:
                return nodes.StandardNode(
                    self.meta,
                    var,
                    datatype,
                    ns_map,
                    self.config,
                    var.nillable,
                    derived_factory if derived else None,
                )

            node = None
            clazz: type | None = None
            if xsi_type:
                clazz = self.context.find_type(xsi_type)

            if clazz:
                node = self.build_element_node(
                    clazz,
                    derived,
                    var.nillable,
                    attrs,
                    ns_map,
                    position,
                    derived_factory,
                    xsi_type,
                    xsi_nil,
                )

            if node:
                return node

            if var.process_contents != "skip":
                clazz = self.context.find_type(qname)

            if clazz:
                node = self.build_element_node(
                    clazz,
                    False,
                    var.nillable,
                    attrs,
                    ns_map,
                    position,
                    None,
                    xsi_type,
                    xsi_nil,
                )

            if node:
                return node

            return nodes.WildcardNode(
                var=var,
                attrs=attrs,
                ns_map=ns_map,
                position=position,
                factory=self.context.class_type.any_element,
            )

        def build_element_node(
            self,
            clazz: type,
            derived: bool,
            nillable: bool,
            attrs: dict,
            ns_map: dict,
            position: int,
            derived_factory: type | None,
            xsi_type: str | None = None,
            xsi_nil: bool | None = None,
        ) -> ElementNode | None:
            """Build the next element child node.

            Args:
                clazz: The target class
                derived: Whether derived elements should wrap the parsed object
                nillable: Specifies whether nil content is allowed
                attrs: The element attributes
                ns_map: The element namespace prefix-URI map
                position: The current length of the intermediate objects
                derived_factory: The derived factory
                xsi_type: The xml type substitution
                xsi_nil: Specifies whether the node supports nillable content

            Returns:
                The next child element node instance, or None if the
                clazz doesn't match the starting element.
            """
            meta = self.context.fetch(clazz, self.meta.namespace, xsi_type)
            nillable = nillable or meta.nillable

            if not meta or (xsi_nil is not None and nillable != xsi_nil):
                return None

            if xsi_type and not derived and not issubclass(meta.clazz, clazz):
                derived = True

            return ElementNode(
                meta=meta,
                config=self.config,
                attrs=attrs,
                ns_map=ns_map,
                context=self.context,
                position=position,
                derived_factory=derived_factory if derived else None,
                xsi_type=xsi_type,
                xsi_nil=xsi_nil,
                mixed=self.meta.mixed_content,
            )

#### `__init__(meta, attrs, ns_map, config, context, position, mixed=False, derived_factory=None, xsi_type=None, xsi_nil=None)`

Initialize the xml node.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def __init__(
        self,
        meta: XmlMeta,
        attrs: dict,
        ns_map: dict,
        config: ParserConfig,
        context: XmlContext,
        position: int,
        mixed: bool = False,
        derived_factory: type | None = None,
        xsi_type: str | None = None,
        xsi_nil: bool | None = None,
    ):
        """Initialize the xml node."""
        self.meta = meta
        self.attrs = attrs
        self.ns_map = ns_map
        self.config = config
        self.context = context
        self.position = position
        self.mixed = mixed
        self.derived_factory = derived_factory
        self.xsi_type = xsi_type
        self.xsi_nil = xsi_nil
        self.assigned: set[int] = set()
        self.tail_processed: bool = False

#### `bind(qname, text, tail, objects)`

Bind the parsed data into an object for the ending element.

This entry point is called when a xml element ends and is responsible to parse the current element attributes/text, bind any children objects and initialize new object.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`qname` | `str` | The element qualified name | required
`text` | `str | None` | The element text content | required
`tail` | `str | None` | The element tail content | required
`objects` | `list[Any]` | The list of intermediate parsed objects | required

Returns:

Type | Description
--- | ---
`bool` | Whether the binding process was successful or not.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind(
        self,
        qname: str,
        text: str | None,
        tail: str | None,
        objects: list[Any],
    ) -> bool:
        """Bind the parsed data into an object for the ending element.

        This entry point is called when a xml element ends and is
        responsible to parse the current element attributes/text, bind
        any children objects and initialize new object.

        Args:
            qname: The element qualified name
            text: The element text content
            tail: The element tail content
            objects: The list of intermediate parsed objects

        Returns:
            Whether the binding process was successful or not.
        """
        obj: Any = None
        if not self.xsi_nil or self.meta.nillable:
            params: dict = {}
            self.bind_attrs(params)
            self.bind_content(params, text, tail, objects)
            obj = self.config.class_factory(self.meta.clazz, params)

        if self.derived_factory:
            obj = self.derived_factory(qname=qname, value=obj, type=self.xsi_type)

        objects.append((qname, obj))

        if not self.tail_processed:
            tail = ParserUtils.normalize_content(tail)
            if tail:
                objects.append((None, tail))

        return True

#### `bind_content(params, text, tail, objects)`

Parse the text and tail content.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict` | The class parameters | required
`text` | `str | None` | The element text content | required
`tail` | `str | None` | The element tail content | required
`objects` | `list[Any]` | The list of intermediate parsed objects | required

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind_content(
        self,
        params: dict,
        text: str | None,
        tail: str | None,
        objects: list[Any],
    ) -> None:
        """Parse the text and tail content.

        Args:
            params: The class parameters
            text: The element text content
            tail: The element tail content
            objects: The list of intermediate parsed objects
        """
        wild_var = self.meta.find_any_wildcard()
        if wild_var and wild_var.mixed:
            self.bind_mixed_objects(params, wild_var, objects)
            bind_text = False
        else:
            self.bind_objects(params, objects)
            bind_text = self.bind_text(params, text)

        if not bind_text and wild_var:
            self.bind_wild_text(params, wild_var, text, tail)

        for key in params:
            if isinstance(params[key], PendingCollection):
                params[key] = params[key].evaluate()

#### `bind_attrs(params)`

Parse the element attributes.

Scenarios

- Each attribute matches a class field
- Class has a wildcard field that sucks everything else

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict[str, Any]` | The class parameters | required

Raises:

Type | Description
--- | ---
`ParserError` | If the document contains an unknown attribute and the configuration is strict.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind_attrs(self, params: dict[str, Any]) -> None:
        """Parse the element attributes.

        Scenarios:
            - Each attribute matches a class field
            - Class has a wildcard field that sucks everything else

        Args:
            params: The class parameters

        Raises:
            ParserError: If the document contains an unknown attribute
                and the configuration is strict.
        """
        if not self.attrs:
            return

        for qname, value in self.attrs.items():
            var = self.meta.find_attribute(qname)
            if var and var.name not in params:
                self.bind_attr(params, var, value)
            else:
                var = self.meta.find_any_attributes(qname)
                if var:
                    self.bind_any_attr(params, var, qname, value)
                else:
                    if (
                        self.config.fail_on_unknown_attributes
                        and target_uri(qname) != Namespace.XSI.uri
                    ):
                        raise ParserError(
                            f"Unknown attribute {self.meta.qname}:{qname}"
                        )

#### `bind_attr(params, var, value)`

Parse an element attribute.

Ignores fields with init==false!

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict` | The class parameters | required
`var` | `XmlVar` | The xml var instance | required
`value` | `Any` | The attribute value | required

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind_attr(self, params: dict, var: XmlVar, value: Any) -> None:
        """Parse an element attribute.

        Ignores fields with init==false!

        Args:
            params: The class parameters
            var: The xml var instance
            value: The attribute value
        """
        value = ParserUtils.parse_var(
            meta=self.meta,
            var=var,
            config=self.config,
            value=value,
            ns_map=self.ns_map,
        )

        if var.init:
            params[var.name] = value
        else:
            ParserUtils.validate_fixed_value(self.meta, var, value)

#### `bind_any_attr(params, var, qname, value)`

Parse an element attribute to a wildcard field.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict` | The class parameters | required
`var` | `XmlVar` | The xml var instance | required
`qname` | `str` | The attribute namespace qualified name | required
`value` | `Any` | The attribute value | required

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind_any_attr(self, params: dict, var: XmlVar, qname: str, value: Any) -> None:
        """Parse an element attribute to a wildcard field.

        Args:
            params: The class parameters
            var: The xml var instance
            qname:  The attribute namespace qualified name
            value: The attribute value
        """
        if var.name not in params:
            params[var.name] = {}

        params[var.name][qname] = ParserUtils.parse_any_attribute(value, self.ns_map)

#### `bind_objects(params, objects)`

Bind children objects.

Emit a warning if an object doesn't fit in any class parameters.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict` | The class parameters | required
`objects` | `list` | The list of intermediate parsed objects | required

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind_objects(self, params: dict, objects: list) -> None:
        """Bind children objects.

        Emit a warning if an object doesn't fit in any
        class parameters.

        Args:
            params: The class parameters
            objects: The list of intermediate parsed objects
        """
        position = self.position
        for qname, obj in objects[position:]:
            if not self.bind_object(params, qname, obj):
                logger.warning("Unassigned parsed object %s", qname)

        del objects[position:]

#### `bind_object(params, qname, value)`

Bind a child object.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict` | The class parameters | required
`qname` | `str` | The qualified name of the element | required
`value` | `Any` | The parsed object | required

Returns:

Type | Description
--- | ---
`bool` | Whether the parsed object can fit in one of class
`bool` | parameters or not.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind_object(self, params: dict, qname: str, value: Any) -> bool:
        """Bind a child object.

        Args:
            params: The class parameters
            qname: The qualified name of the element
            value: The parsed object

        Returns:
            Whether the parsed object can fit in one of class
            parameters or not.
        """
        for var in self.meta.find_children(qname):
            if var.is_wildcard:
                return self.bind_wild_var(params, var, qname, value)

            if self.bind_var(params, var, value):
                return True

        return False

#### `bind_var(params, var, value)` `classmethod`

Bind a child object to an element field.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict` | The class parameters | required
`var` | `XmlVar` | The matched xml var instance | required
`value` | `Any` | The parsed object | required

Returns:

Type | Description
--- | ---
`bool` | Whether the parsed object can fit in one of class
`bool` | parameters or not.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    @classmethod
    def bind_var(cls, params: dict, var: XmlVar, value: Any) -> bool:
        """Bind a child object to an element field.

        Args:
            params: The class parameters
            var: The matched xml var instance
            value: The parsed object

        Returns:
            Whether the parsed object can fit in one of class
            parameters or not.
        """
        if var.init:
            if var.list_element:
                items = params.get(var.name)
                if items is None:
                    params[var.name] = PendingCollection([value], var.factory)
                else:
                    items.append(value)
            elif var.name not in params:
                params[var.name] = value
            else:
                return False

        return True

#### `bind_wild_var(params, var, qname, value)`

Bind a child object to a wildcard field.

The wildcard might support one or more values. If it supports only one the values are nested under a parent generic element instance.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict` | The class parameters | required
`var` | `XmlVar` | The wildcard var instance | required
`qname` | `str` | The qualified name of the element | required
`value` | `Any` | The parsed value | required

Returns:

Type | Description
--- | ---
`bool` | Always true, since wildcard fields can absorb any value.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind_wild_var(self, params: dict, var: XmlVar, qname: str, value: Any) -> bool:
        """Bind a child object to a wildcard field.

        The wildcard might support one or more values. If it
        supports only one the values are nested under a parent
        generic element instance.

        Args:
            params: The class parameters
            var: The wildcard var instance
            qname: The qualified name of the element
            value: The parsed value

        Returns:
            Always true, since wildcard fields can absorb any value.
        """
        value = self.prepare_generic_value(qname, value)

        if var.list_element:
            items = params.get(var.name)
            if items is None:
                params[var.name] = PendingCollection([value], var.factory)
            else:
                items.append(value)
        elif var.name in params:
            previous = params[var.name]
            factory = self.context.class_type.any_element

            if not isinstance(previous, factory) or previous.qname:
                params[var.name] = factory(children=[previous])

            params[var.name].children.append(value)
        else:
            params[var.name] = value

        return True

#### `bind_mixed_objects(params, var, objects)`

Bind children objects to a mixed content wildcard field.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict` | The class parameters | required
`var` | `XmlVar` | The wildcard var instance | required
`objects` | `list` | The list of intermediate parsed objects | required

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind_mixed_objects(self, params: dict, var: XmlVar, objects: list) -> None:
        """Bind children objects to a mixed content wildcard field.

        Args:
            params: The class parameters
            var: The wildcard var instance
            objects: The list of intermediate parsed objects
        """
        pos = self.position
        params[var.name] = list(starmap(self.prepare_generic_value, objects[pos:]))
        del objects[pos:]

#### `prepare_generic_value(qname, value)`

Wrap primitive text nodes in a generic element.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`qname` | `str | None` | The qualified name of the element | required
`value` | `Any` | The parsed object | required

Returns:

Type | Description
--- | ---
`Any` | The original parsed value if it's a data class, or
`Any` | the wrapped primitive value in a generic element.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def prepare_generic_value(self, qname: str | None, value: Any) -> Any:
        """Wrap primitive text nodes in a generic element.

        Args:
            qname: The qualified name of the element
            value: The parsed object

        Returns:
            The original parsed value if it's a data class, or
            the wrapped primitive value in a generic element.
        """
        if qname and not self.context.class_type.is_model(value):
            any_factory = self.context.class_type.any_element
            value = any_factory(qname=qname, text=converter.serialize(value))

        return value

#### `bind_text(params, text)`

Bind the element text content.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict` | The class parameters | required
`text` | `str | None` | The element text content | required

Returns:

Type | Description
--- | ---
`bool` | Whether the text content can fit in one of class
`bool` | parameters or not.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind_text(self, params: dict, text: str | None) -> bool:
        """Bind the element text content.

        Args:
            params: The class parameters
            text: The element text content

        Returns:
            Whether the text content can fit in one of class
            parameters or not.
        """
        var = self.meta.text

        if not var or (text is None and not self.xsi_nil):
            return False

        if self.xsi_nil and not text:
            value = None
        else:
            value = ParserUtils.parse_var(
                meta=self.meta,
                var=var,
                config=self.config,
                value=text,
                ns_map=self.ns_map,
            )

        if var.init:
            params[var.name] = value
        else:
            ParserUtils.validate_fixed_value(self.meta, var, value)

        return True

#### `bind_wild_text(params, var, text, tail)`

Bind the element text and tail content to a wildcard field.

If the field is a list, prepend the text. Otherwise, build a generic element with the text/tail content and any attributes. If the field is already occupied, then this means the current node is a child, and we need to nested them.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`params` | `dict` | The class parameters | required
`var` | `XmlVar` | The wildcard var instance | required
`text` | `str | None` | The element text content | required
`tail` | `str | None` | The element text content | required

Returns:

Type | Description
--- | ---
`bool` | Whether the text content can fit in one of class
`bool` | parameters or not.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def bind_wild_text(
        self,
        params: dict,
        var: XmlVar,
        text: str | None,
        tail: str | None,
    ) -> bool:
        """Bind the element text and tail content to a wildcard field.

        If the field is a list, prepend the text.
        Otherwise, build a generic element with the text/tail content
        and any attributes. If the field is already occupied, then this
        means the current node is a child, and we need to nested them.

        Args:
            params: The class parameters
            var: The wildcard var instance
            text: The element text content
            tail: The element text content

        Returns:
            Whether the text content can fit in one of class
            parameters or not.
        """
        text = ParserUtils.normalize_content(text)
        tail = ParserUtils.normalize_content(tail)
        if text is tail is None:
            return False

        if var.list_element:
            items = params.get(var.name)
            if items is None:
                params[var.name] = items = PendingCollection(None, var.factory)

            items.insert(0, text)

        else:
            previous = params.get(var.name, None)
            factory = self.context.class_type.any_element
            generic = factory(
                text=text,
                tail=tail,
                attributes=ParserUtils.parse_any_attributes(self.attrs, self.ns_map),
            )
            if previous:
                generic.children.append(previous)

            params[var.name] = generic
            self.tail_processed = True

        return True

#### `child(qname, attrs, ns_map, position)`

Initialize the next child node to be queued, when an element starts.

This entry point is responsible to create the next node type with all the necessary information on how to bind the incoming input data.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`qname` | `str` | The element qualified name | required
`attrs` | `dict` | The element attributes | required
`ns_map` | `dict` | The element namespace prefix-URI map | required
`position` | `int` | The current length of the intermediate objects | required

Raises:

Type | Description
--- | ---
`ParserError` | If the child element is unknown

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def child(self, qname: str, attrs: dict, ns_map: dict, position: int) -> XmlNode:
        """Initialize the next child node to be queued, when an element starts.

        This entry point is responsible to create the next node type
        with all the necessary information on how to bind the incoming
        input data.

        Args:
            qname: The element qualified name
            attrs: The element attributes
            ns_map: The element namespace prefix-URI map
            position: The current length of the intermediate objects

        Raises:
            ParserError: If the child element is unknown
        """
        for var in self.meta.find_children(qname):
            unique = 0 if not var.is_element or var.list_element else var.index
            if not unique or unique not in self.assigned:
                node = self.build_node(qname, var, attrs, ns_map, position)

                if node:
                    if unique:
                        self.assigned.add(unique)

                    return node

        if self.config.fail_on_unknown_properties:
            raise ParserError(f"Unknown property {self.meta.qname}:{qname}")

        return nodes.SkipNode()

#### `build_node(qname, var, attrs, ns_map, position)`

Build the next child node based on the xml var instance.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`qname` | `str` | The element qualified name | required
`var` | `XmlVar` | The xml var instance | required
`attrs` | `dict` | The element attributes | required
`ns_map` | `dict` | The element namespace prefix-URI map | required
`position` | `int` | The current length of the intermediate objects | required

Returns:

Type | Description
--- | ---
`XmlNode | None` | The next child node instance, or None if nothing matched
`XmlNode | None` | the starting element.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def build_node(
        self,
        qname: str,
        var: XmlVar,
        attrs: dict,
        ns_map: dict,
        position: int,
    ) -> XmlNode | None:
        """Build the next child node based on the xml var instance.

        Args:
            qname: The element qualified name
            var: The xml var instance
            attrs: The element attributes
            ns_map: The element namespace prefix-URI map
            position: The current length of the intermediate objects

        Returns:
            The next child node instance, or None if nothing matched
            the starting element.
        """
        if var.is_clazz_union:
            return nodes.UnionNode(
                meta=self.meta,
                var=var,
                attrs=attrs,
                ns_map=ns_map,
                config=self.config,
                context=self.context,
                position=position,
            )

        xsi_type = ParserUtils.xsi_type(attrs, ns_map)
        xsi_nil = ParserUtils.xsi_nil(attrs)
        derived_factory = self.context.class_type.derived_element

        if var.clazz:
            return self.build_element_node(
                var.clazz,
                False,
                var.nillable,
                attrs,
                ns_map,
                position,
                derived_factory,
                xsi_type,
                xsi_nil,
            )

        if not var.any_type and not var.is_wildcard:
            return nodes.PrimitiveNode(self.meta, var, ns_map, self.config)

        datatype = DataType.from_qname(xsi_type) if xsi_type else None
        derived = var.is_wildcard
        if datatype:
            return nodes.StandardNode(
                self.meta,
                var,
                datatype,
                ns_map,
                self.config,
                var.nillable,
                derived_factory if derived else None,
            )

        node = None
        clazz: type | None = None
        if xsi_type:
            clazz = self.context.find_type(xsi_type)

        if clazz:
            node = self.build_element_node(
                clazz,
                derived,
                var.nillable,
                attrs,
                ns_map,
                position,
                derived_factory,
                xsi_type,
                xsi_nil,
            )

        if node:
            return node

        if var.process_contents != "skip":
            clazz = self.context.find_type(qname)

        if clazz:
            node = self.build_element_node(
                clazz,
                False,
                var.nillable,
                attrs,
                ns_map,
                position,
                None,
                xsi_type,
                xsi_nil,
            )

        if node:
            return node

        return nodes.WildcardNode(
            var=var,
            attrs=attrs,
            ns_map=ns_map,
            position=position,
            factory=self.context.class_type.any_element,
        )

#### `build_element_node(clazz, derived, nillable, attrs, ns_map, position, derived_factory, xsi_type=None, xsi_nil=None)`

Build the next element child node.

Parameters:

Name | Type | Description | Default
--- | --- | --- | ---
`clazz` | `type` | The target class | required
`derived` | `bool` | Whether derived elements should wrap the parsed object | required
`nillable` | `bool` | Specifies whether nil content is allowed | required
`attrs` | `dict` | The element attributes | required
`ns_map` | `dict` | The element namespace prefix-URI map | required
`position` | `int` | The current length of the intermediate objects | required
`derived_factory` | `type | None` | The derived factory | required
`xsi_type` | `str | None` | The xml type substitution | `None`
`xsi_nil` | `bool | None` | Specifies whether the node supports nillable content | `None`

Returns:

Type | Description
--- | ---
`ElementNode | None` | The next child element node instance, or None if the
`ElementNode | None` | clazz doesn't match the starting element.

Source code in `xsdata/formats/dataclass/parsers/nodes/element.py`

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    def build_element_node(
        self,
        clazz: type,
        derived: bool,
        nillable: bool,
        attrs: dict,
        ns_map: dict,
        position: int,
        derived_factory: type | None,
        xsi_type: str | None = None,
        xsi_nil: bool | None = None,
    ) -> ElementNode | None:
        """Build the next element child node.

        Args:
            clazz: The target class
            derived: Whether derived elements should wrap the parsed object
            nillable: Specifies whether nil content is allowed
            attrs: The element attributes
            ns_map: The element namespace prefix-URI map
            position: The current length of the intermediate objects
            derived_factory: The derived factory
            xsi_type: The xml type substitution
            xsi_nil: Specifies whether the node supports nillable content

        Returns:
            The next child element node instance, or None if the
            clazz doesn't match the starting element.
        """
        meta = self.context.fetch(clazz, self.meta.namespace, xsi_type)
        nillable = nillable or meta.nillable

        if not meta or (xsi_nil is not None and nillable != xsi_nil):
            return None

        if xsi_type and not derived and not issubclass(meta.clazz, clazz):
            derived = True

        return ElementNode(
            meta=meta,
            config=self.config,
            attrs=attrs,
            ns_map=ns_map,
            context=self.context,
            position=position,
            derived_factory=derived_factory if derived else None,
            xsi_type=xsi_type,
            xsi_nil=xsi_nil,
            mixed=self.meta.mixed_content,
        )