class REXML::Attributes

operations for accessing elements in that set.
A class that defines the set of Attributes of an Element and provides

def [](name)


Related: get_attribute (returns an \Attribute object).

ele.attributes['nosuch'] # => nil
ele.attributes['bar:att'] # => "2"
ele.attributes['att'] # => "<"
ele = d.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

with entities expanded:
The value returned is the unnormalized attribute value,
if it exists; otherwise +nil+.
Returns the value for the attribute given by +name+,

[name] -> attribute_value or nil
:call-seq: 
def [](name)
  attr = get_attribute(name)
  return attr.value unless attr.nil?
  return nil
end

def []=( name, value )


attrs.include?('baz:att') # => false
attrs['baz:att'] = nil

When +value+ is +nil+, deletes the attribute if it exists:

attrs['baz:att'] = '3' # => "3"
attrs['foo:att'] = '2' # => "2"
attrs = ele.attributes
ele = d.root.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

overwriting the previous value if it exists:
assigns that to the attribute for the given +name+,
When +value+ is non-+nil+,

[name] = value -> value
:call-seq: 
def []=( name, value )
  if value.nil?             # Delete the named attribute
    attr = get_attribute(name)
    delete attr
    return
  end
  unless value.kind_of? Attribute
    if @element.document and @element.document.doctype
      value = Text::normalize( value, @element.document.doctype )
    else
      value = Text::normalize( value, nil )
    end
    value = Attribute.new(name, value)
  end
  value.element = @element
  old_attr = fetch(value.name, nil)
  if old_attr.nil?
    store(value.name, value)
  elsif old_attr.kind_of? Hash
    old_attr[value.prefix] = value
  elsif old_attr.prefix != value.prefix
    store value.name, {old_attr.prefix => old_attr,
                       value.prefix    => value}
  else
    store value.name, value
  end
  return @element
end

def add( attribute )


attrs.include?('baz') # => true
attrs.add(REXML::Attribute.new('baz', '3')) # => baz='3'
attrs.add(REXML::Attribute.new('foo:att', '2')) # => foo:att='2'
attrs # => {"att"=>{"foo"=>foo:att='1', "bar"=>bar:att='2', ""=>att='<'}}
attrs = ele.attributes
ele = d.root.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

returns +attribute+:
attribute of the same name if it exists;
Adds attribute +attribute+, replacing the previous

add(attribute) -> attribute
:call-seq: 
def add( attribute )
  self[attribute.name] = attribute
end

def delete( attribute )


attrs.delete(attr) # => # =>
attrs.delete(attr) # => # =>
attr = REXML::Attribute.new('bar:att', '2')

removes that attribute if it exists:
When attribute argument +attribute+ is given,

attrs.delete('foo:att') # =>
attrs.delete('foo:att') # =>
attrs = ele.attributes
ele = d.root.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

removes the attribute of that name if it exists:
When string argument +name+ is given,

returns the attributes' element.
Removes a specified attribute if it exists;

delete(attribute) -> element
delete(name) -> element
:call-seq: 
def delete( attribute )
  name = nil
  prefix = nil
  if attribute.kind_of? Attribute
    name = attribute.name
    prefix = attribute.prefix
  else
    attribute =~ Namespace::NAMESPLIT
    prefix, name = $1, $2
    prefix = '' unless prefix
  end
  old = fetch(name, nil)
  if old.kind_of? Hash # the supplied attribute is one of many
    old.delete(prefix)
    if old.size == 1
      repl = nil
      old.each_value{|v| repl = v}
      store name, repl
    end
  elsif old.nil?
    return @element
  else # the supplied attribute is a top-level one
    super(name)
  end
  @element
end

def delete_all( name )


attrs.delete_all('att') # => [att='<']
attrs = ele.attributes
ele = d.root.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

returns an array of the removed attributes:
Removes all attributes matching the given +name+;

delete_all(name) -> array_of_removed_attributes
:call-seq: 
def delete_all( name )
  rv = []
  each_attribute { |attribute|
    rv << attribute if attribute.expanded_name == name
  }
  rv.each{ |attr| attr.remove }
  return rv
end

def each


["att", "<"]
["bar:att", "2"]
["foo:att", "1"]

Output:

end
p [expanded_name, value]
ele.attributes.each do |expanded_name, value|
ele = d.root.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

Calls the given block with each expanded-name/value pair:

each {|expanded_name, value| ... }
:call-seq: 
def each
  return to_enum(__method__) unless block_given?
  each_attribute do |attr|
    yield [attr.expanded_name, attr.value]
  end
end

def each_attribute # :yields: attribute

:yields: attribute

[REXML::Attribute, att='<']
[REXML::Attribute, bar:att='2']
[REXML::Attribute, foo:att='1']

Output:

end
p [attr.class, attr]
ele.attributes.each_attribute do |attr|
ele = d.root.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

Calls the given block with each \REXML::Attribute object:

each_attribute {|attr| ... }
:call-seq: 
def each_attribute # :yields: attribute
  return to_enum(__method__) unless block_given?
  each_value do |val|
    if val.kind_of? Attribute
      yield val
    else
      val.each_value { |atr| yield atr }
    end
  end
end

def get_attribute( name )


attrs.get_attribute('nosuch') # => nil
attrs.get_attribute('att') # => att='<'
attrs.get_attribute('bar:att') # => bar:att='2'
attrs.get_attribute('foo:att').class # => REXML::Attribute
attrs.get_attribute('foo:att') # => foo:att='1'
attrs = ele.attributes
ele = d.root.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

Returns the \REXML::Attribute object for the given +name+:

get_attribute(name) -> attribute_object or nil
:call-seq: 
def get_attribute( name )
  attr = fetch( name, nil )
  if attr.nil?
    return nil if name.nil?
    # Look for prefix
    name =~ Namespace::NAMESPLIT
    prefix, n = $1, $2
    if prefix
      attr = fetch( n, nil )
      # check prefix
      if attr == nil
      elsif attr.kind_of? Attribute
        return attr if prefix == attr.prefix
      else
        attr = attr[ prefix ]
        return attr
      end
    end
    element_document = @element.document
    if element_document and element_document.doctype
      expn = @element.expanded_name
      expn = element_document.doctype.name if expn.size == 0
      attr_val = element_document.doctype.attribute_of(expn, name)
      return Attribute.new( name, attr_val ) if attr_val
    end
    return nil
  end
  if attr.kind_of? Hash
    attr = attr[ @element.prefix ]
  end
  return attr
end

def get_attribute_ns(namespace, name)


attrs.get_attribute_ns('http://foo', 'nosuch') # => nil
attrs.get_attribute_ns('http://foo', 'att') # => foo:att='1'
attrs = ele.attributes
ele = d.root.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

that matches the given +namespace+ and +name+:
Returns the \REXML::Attribute object among the attributes

get_attribute_ns(namespace, name)
:call-seq: 
def get_attribute_ns(namespace, name)
  result = nil
  each_attribute() { |attribute|
    if name == attribute.name &&
      namespace == attribute.namespace() &&
      ( !namespace.empty? || !attribute.fully_expanded_name.index(':') )
      # foo will match xmlns:foo, but only if foo isn't also an attribute
      result = attribute if !result or !namespace.empty? or
                            !attribute.fully_expanded_name.index(':')
    end
  }
  result
end

def initialize element


- +element.expanded_name+.
- +element.prefix+.
- +element.document+.

Other instance methods in class \REXML::Attributes may refer to:

attrs.object_id == ele.attributes.object_id # => false
attrs = REXML::Attributes.new(ele)
ele = REXML::Element.new('foo')

but its own attributes are not modified:
The element given by argument +element+ is stored,
Creates and returns a new \REXML::Attributes object.

new(element)
:call-seq: 
def initialize element
  @element = element
end

def length


ele.attributes.length # => 3
ele = d.root.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

Returns the count of attributes:

length
:call-seq: 
def length
  c = 0
  each_attribute { c+=1 }
  c
end

def namespaces


d.root.attributes.namespaces # => {"xmlns"=>"foo", "x"=>"bar", "y"=>"twee"}
d = REXML::Document.new(xml_string)
xml_string = ''

Returns a hash of name/value pairs for the namespaces:

namespaces
:call-seq: 
def namespaces
  namespaces = {}
  each_attribute do |attribute|
    namespaces[attribute.name] = attribute.value if attribute.prefix == 'xmlns' or attribute.name == 'xmlns'
  end
  if @element.document and @element.document.doctype
    expn = @element.expanded_name
    expn = @element.document.doctype.name if expn.size == 0
    @element.document.doctype.attributes_of(expn).each {
      |attribute|
      namespaces[attribute.name] = attribute.value if attribute.prefix == 'xmlns' or attribute.name == 'xmlns'
    }
  end
  namespaces
end

def prefixes


d.root.attributes.prefixes # => ["x", "y"]
d = REXML::Document.new(xml_string)
xml_string = ''

namespace declaration, if one exists.
The array does not include the default
Returns an array of prefix strings in the attributes.

prefixes -> array_of_prefix_strings
:call-seq: 
def prefixes
  ns = []
  each_attribute do |attribute|
    ns << attribute.name if attribute.prefix == 'xmlns'
  end
  if @element.document and @element.document.doctype
    expn = @element.expanded_name
    expn = @element.document.doctype.name if expn.size == 0
    @element.document.doctype.attributes_of(expn).each {
      |attribute|
      ns << attribute.name if attribute.prefix == 'xmlns'
    }
  end
  ns
end

def to_a


attrs.first.class # => REXML::Attribute
attrs = ele.attributes.to_a # => [foo:att='1', bar:att='2', att='<']
ele = d.root.elements['//ele'] # =>
d = REXML::Document.new(xml_string)
EOT



xml_string = <<-EOT

the attributes:
Returns an array of \REXML::Attribute objects representing

to_a -> array_of_attribute_objects
:call-seq: 
def to_a
  enum_for(:each_attribute).to_a
end