# class XML::Node

- XML::Node
- Reference
- Object

##
Direct Known Subclasses

- XML::Document

##
Defined in:

xml/node.cr
xml/node/type.cr

##
Constant Summary

LOOKS_LIKE_XPATH = `/^(\.\/|\/|\.\.|\.$)/`

##
Instance Method Summary

- #==(other : Node)

  Compares with other.

- #[](attribute : String) : String

  Gets the attribute content for the attribute given by name.

- #[]=(name : String, value)

  Sets attribute of this node to value.

- #[]?(attribute : String) : String | Nil

  Gets the attribute content for the attribute given by name.

- #attribute? : Bool

  Returns `true` if this is an attribute node.

- #attributes : XML::Attributes

  Returns attributes of this node as an `XML::Attributes`.

- #cdata? : Bool

  Returns `true` if this is a `CDATA` section node.

- #children : XML::NodeSet

  Gets the list of children for this node as a `XML::NodeSet`.

- #comment?

  Returns `true` if this is a comment node.

- #content : String

  Returns the content for this Node.

- #content=(content)

  Sets the Node's content to a Text node containing string.

- #delete(name : String) : String | Nil

  Deletes attribute given by name.

- #document : Document

  Gets the document for this node.

- #document? : Bool

  Returns `true` if this is a Document or HTML Document node.

- #element? : Bool

  Returns `true` if this is an Element node.

- #encoding : String | Nil

  Returns the encoding of this node's document.

- #errors : Array(XML::Error) | Nil

  DEPRECATED Use XML::Document#errors instead.

- #first_element_child : XML::Node | Nil

  Returns the first child node of this node that is an element.

- #fragment? : Bool

  Returns `true` if this is a DocumentFragment.

- #hash(hasher)

  See `Object#hash(hasher)`

- #inner_text : String

  Returns the content for this Node.

- #inspect(io : IO) : Nil

  Returns detailed information for this node including node type, name, attributes and children.

- #name : String

  Returns the name for this Node.

- #name=(name)

  Sets the name for this Node.

- #namespace : Namespace | Nil

  Returns the namespace for this node or `nil` if not found.

- #namespace_definitions : Array(Namespace)

  Returns namespaces defined on this node directly.

- #namespace_scopes : Array(Namespace)

  Returns namespaces in scope for this node – those defined on this node directly or any ancestor node – as an `Array` of `XML::Namespace` objects.

- #namespaces : Hash(String, String | Nil)

  Returns a `Hash(String, String?) of prefix => href` for all namespaces on this node and its ancestors.

- #next : XML::Node | Nil

  Returns the next sibling node or `nil` if not found.

- #next_element : XML::Node | Nil

  Returns the next element node sibling or `nil` if not found.

- #next_sibling : XML::Node | Nil

  Returns the next sibling node or `nil` if not found.

- #object_id : UInt64

  Returns the address of underlying `LibXML::Node*` in memory.

- #parent : XML::Node | Nil

  Returns the parent node or `nil` if not found.

- #pretty_print(pp : PrettyPrint) : Nil

  Pretty prints `self` into the given printer.

- #previous : XML::Node | Nil

  Returns the previous sibling node or `nil` if not found.

- #previous_element : XML::Node | Nil

  Returns the previous sibling node that is an element or `nil` if not found.

- #previous_sibling : XML::Node | Nil

  Returns the previous sibling node or `nil` if not found.

- #processing_instruction?

  Returns `true` if this is a Processing Instruction node.

- #root : XML::Node | Nil

  Returns the root node for this document or `nil`.

- #text : String

  Same as `#content`.

- #text=(text)

  Same as `#content=`.

- #text? : Bool

  Returns `true` if this is a Text node.

- #to_s(io : IO) : Nil

  Serialize this Node as XML to io using default options.

- #to_xml(indent : Int = 2, indent_text = " ", options : SaveOptions = SaveOptions.xml_default) : String

  Serialize this Node as XML and return a `String` using default options.

- #to_xml(io : IO, indent = 2, indent_text = " ", options : SaveOptions = SaveOptions.xml_default)

  Serialize this Node as XML to io using default options.

- #type : XML::Node::Type

  Returns the type for this Node as `XML::Node::Type`.

- #unlink : Nil

  Removes the node from the XML document.

- #version : String | Nil

  Returns the version of this node's document.

- #xml?

  Returns `true` if this is an xml Document node.

- #xpath(path, namespaces = nil, variables = nil)

  Searches this node for XPath path.

- #xpath_bool(path, namespaces = nil, variables = nil)

  Searches this node for XPath path and restricts the return type to `Bool`.

- #xpath_float(path, namespaces = nil, variables = nil)

  Searches this node for XPath path and restricts the return type to `Float64`.

- #xpath_node(path, namespaces = nil, variables = nil)

  Searches this node for XPath path for nodes and returns the first one.

- #xpath_nodes(path, namespaces = nil, variables = nil)

  Searches this node for XPath path and restricts the return type to `NodeSet`.

- #xpath_string(path, namespaces = nil, variables = nil)

  Searches this node for XPath path and restricts the return type to `String`.

### Instance methods inherited from class `Reference`

==(other : self)
==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup, hash(hasher) hash, initialize initialize, inspect(io : IO) : Nil inspect, object_id : UInt64 object_id, pretty_print(pp) : Nil pretty_print, same?(other : Reference) : Bool
same?(other : Nil) same?, to_s(io : IO) : Nil to_s

### Constructor methods inherited from class `Reference`

new new, unsafe_construct(address : Pointer, *args, **opts) : self unsafe_construct

### Class methods inherited from class `Reference`

pre_initialize(address : Pointer) pre_initialize

### Instance methods inherited from class `Object`

! : Bool !, !=(other) !=, !~(other) !~, ==(other) ==, ===(other : JSON::Any)
===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash(hasher)
hash hash, in?(collection : Object) : Bool
in?(*values : Object) : Bool in?, inspect(io : IO) : Nil
inspect : String inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil!(message)
not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO) : Nil
to_json : String to_json, to_pretty_json(indent : String = " ") : String
to_pretty_json(io : IO, indent : String = " ") : Nil to_pretty_json, to_s(io : IO) : Nil
to_s : String to_s, to_yaml(io : IO) : Nil
to_yaml : String to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as

### Class methods inherited from class `Object`

from_json(string_or_io : String | IO, root : String)
from_json(string_or_io : String | IO) from_json, from_yaml(string_or_io : String | IO) from_yaml

### Macros inherited from class `Object`

class_getter(*names, &block) class_getter, class_getter!(*names) class_getter!, class_getter?(*names, &block) class_getter?, class_property(*names, &block) class_property, class_property!(*names) class_property!, class_property?(*names, &block) class_property?, class_setter(*names) class_setter, def_clone def_clone, def_equals(*fields) def_equals, def_equals_and_hash(*fields) def_equals_and_hash, def_hash(*fields) def_hash, delegate(*methods, to object) delegate, forward_missing_to(delegate) forward_missing_to, getter(*names, &block) getter, getter!(*names) getter!, getter?(*names, &block) getter?, property(*names, &block) property, property!(*names) property!, property?(*names, &block) property?, setter(*names) setter

##
Instance Method Detail

def ==(other : Node) #

Compares with other.

def [](attribute : String) : String #

Gets the attribute content for the attribute given by name. Raises `KeyError` if attribute is not found.

def []=(name : String, value) #

Sets attribute of this node to value. Raises `XML::Error` if this node does not support attributes.

def []?(attribute : String) : String | Nil #

Gets the attribute content for the attribute given by name. Returns `nil` if attribute is not found.

def attribute? : Bool #

Returns `true` if this is an attribute node.

def attributes : XML::Attributes #

Returns attributes of this node as an `XML::Attributes`.

def cdata? : Bool #

Returns `true` if this is a `CDATA` section node.

def children : XML::NodeSet #

Gets the list of children for this node as a `XML::NodeSet`.

def comment? #

Returns `true` if this is a comment node.

def content : String #

Returns the content for this Node. An empty string is returned if the node has no content.

def content=(content) #

Sets the Node's content to a Text node containing string. The string gets XML escaped, not interpreted as markup.

def delete(name : String) : String | Nil #

Deletes attribute given by name. Returns attributes value, or `nil` if attribute not found.

def document : Document #

Gets the document for this node.

def document? : Bool #

Returns `true` if this is a Document or HTML Document node.

def element? : Bool #

Returns `true` if this is an Element node.

def encoding : String | Nil #

Returns the encoding of this node's document.

def errors : Array(XML::Error) | Nil #

DEPRECATED Use XML::Document#errors instead.

def first_element_child : XML::Node | Nil #

Returns the first child node of this node that is an element. Returns `nil` if not found.

def fragment? : Bool #

Returns `true` if this is a DocumentFragment.

def hash(hasher) #

See `Object#hash(hasher)`

def inner_text : String #

Returns the content for this Node.

def inspect(io : IO) : Nil #

Returns detailed information for this node including node type, name, attributes and children.

def name : String #

Returns the name for this Node.

def name=(name) #

Sets the name for this Node.

def namespace : Namespace | Nil #

Returns the namespace for this node or `nil` if not found.

def namespace_definitions : Array(Namespace) #

Returns namespaces defined on this node directly.

def namespace_scopes : Array(Namespace) #

Returns namespaces in scope for this node – those defined on this node directly or any ancestor node – as an `Array` of `XML::Namespace` objects.

Default namespaces (`"xmlns="` style) for this node are included in this array; default namespaces for ancestors, however, are not.

See also `#namespaces`

def namespaces : Hash(String, String | Nil) #

Returns a `Hash(String, String?) of prefix => href` for all namespaces on this node and its ancestors.

This method returns the same namespaces as `#namespace_scopes`.

Returns namespaces in scope for this node – those defined on this node directly or any ancestor node – as a `Hash` of attribute-name/value pairs.

NOTE Note that the keys in this hash XML attributes that would be used to define this namespace, such as `"xmlns:prefix"`, not just the prefix.

def next : XML::Node | Nil #

Returns the next sibling node or `nil` if not found.

def next_element : XML::Node | Nil #

Returns the next element node sibling or `nil` if not found.

def next_sibling : XML::Node | Nil #

Returns the next sibling node or `nil` if not found.

def object_id : UInt64 #

Returns the address of underlying `LibXML::Node*` in memory.

def parent : XML::Node | Nil #

Returns the parent node or `nil` if not found.

def pretty_print(pp : PrettyPrint) : Nil #
Description copied from class Object

Pretty prints `self` into the given printer.

By default appends a text that is the result of invoking `#inspect` on `self`. Subclasses should override for custom pretty printing.

def previous : XML::Node | Nil #

Returns the previous sibling node or `nil` if not found.

def previous_element : XML::Node | Nil #

Returns the previous sibling node that is an element or `nil` if not found.

def previous_sibling : XML::Node | Nil #

Returns the previous sibling node or `nil` if not found. Same with `#previous`.

def processing_instruction? #

Returns `true` if this is a Processing Instruction node.

def root : XML::Node | Nil #

Returns the root node for this document or `nil`.

def text : String #

Same as `#content`.

def text=(text) #

Same as `#content=`.

def text? : Bool #

Returns `true` if this is a Text node.

def to_s(io : IO) : Nil #

Serialize this Node as XML to io using default options.

See `#to_xml`.

def to_xml(indent : Int = 2, indent_text = " ", options : SaveOptions = SaveOptions.xml_default) : String #

Serialize this Node as XML and return a `String` using default options.

See `XML::SaveOptions.xml_default` for default options.

def to_xml(io : IO, indent = 2, indent_text = " ", options : SaveOptions = SaveOptions.xml_default) #

Serialize this Node as XML to io using default options.

See `XML::SaveOptions.xml_default` for default options.

def type : XML::Node::Type #

Returns the type for this Node as `XML::Node::Type`.

def unlink : Nil #

Removes the node from the XML document.

def version : String | Nil #

Returns the version of this node's document.

def xml? #

Returns `true` if this is an xml Document node.

def xpath(path, namespaces = nil, variables = nil) #

Searches this node for XPath path. Returns result with appropriate type (`Bool | Float64 | String | XML::NodeSet`).

Raises `XML::Error` on evaluation error.

def xpath_bool(path, namespaces = nil, variables = nil) #

Searches this node for XPath path and restricts the return type to `Bool`.

    require "xml"

    doc = XML.parse("<person></person>")

    doc.xpath_bool("count(//person) > 0") # => true

def xpath_float(path, namespaces = nil, variables = nil) #

Searches this node for XPath path and restricts the return type to `Float64`.

    require "xml"

    doc = XML.parse("<person></person>")

    doc.xpath_float("count(//person)") # => 1.0

def xpath_node(path, namespaces = nil, variables = nil) #

Searches this node for XPath path for nodes and returns the first one. or `nil` if not found

    require "xml"

    doc = XML.parse("<person></person>")

    doc.xpath_node("//person")  # => #<XML::Node:0x2013e80 name="person">
    doc.xpath_node("//invalid") # => nil

def xpath_nodes(path, namespaces = nil, variables = nil) #

Searches this node for XPath path and restricts the return type to `NodeSet`.

    require "xml"

    doc = XML.parse("<person></person>")

    nodes = doc.xpath_nodes("//person")
    nodes.class       # => XML::NodeSet
    nodes.map(&.name) # => ["person"]

def xpath_string(path, namespaces = nil, variables = nil) #

Searches this node for XPath path and restricts the return type to `String`.

    require "xml"

    doc = XML.parse("<person></person>")

    doc.xpath_string("string(/persons/person[1])")