diff --git a/lib/rexml/child.rb b/lib/rexml/child.rb
index cc6e9a47..2718040f 100644
--- a/lib/rexml/child.rb
+++ b/lib/rexml/child.rb
@@ -83,13 +83,12 @@ def previous_sibling=(other)
     # Returns:: the document this child belongs to, or nil if this child
     # belongs to no document
     def document
-      return parent.document unless parent.nil?
-      nil
+      parent&.document
     end
 
     # This doesn't yet handle encodings
     def bytes
-      document.encoding
+      document&.encoding
 
       to_s
     end
diff --git a/lib/rexml/element.rb b/lib/rexml/element.rb
index b62b6cc2..3e9e9d4c 100644
--- a/lib/rexml/element.rb
+++ b/lib/rexml/element.rb
@@ -473,8 +473,7 @@ def root
     # Related: #root, #root_node.
     #
     def document
-      rt = root
-      rt.parent if rt
+      root&.parent
     end
 
     # :call-seq:
@@ -2325,11 +2324,11 @@ def get_attribute( name )
             return attr
           end
         end
-        element_document = @element.document
-        if element_document and element_document.doctype
+        doctype = @element.document&.doctype
+        if doctype
           expn = @element.expanded_name
-          expn = element_document.doctype.name if expn.size == 0
-          attr_val = element_document.doctype.attribute_of(expn, name)
+          expn = doctype.name if expn.size == 0
+          attr_val = doctype.attribute_of(expn, name)
           return Attribute.new( name, attr_val ) if attr_val
         end
         return nil
@@ -2371,8 +2370,8 @@ def []=( name, value )
       end
 
       unless value.kind_of? Attribute
-        if @element.document and @element.document.doctype
-          value = Text::normalize( value, @element.document.doctype )
+        if @element.document and (doctype = @element.document&.doctype)
+          value = Text::normalize( value, doctype )
         else
           value = Text::normalize( value, nil )
         end
@@ -2390,7 +2389,7 @@ def []=( name, value )
       else
         store value.name, value
       end
-      return @element
+      @element
     end
 
     # :call-seq:
@@ -2409,10 +2408,10 @@ def prefixes
       each_attribute do |attribute|
         ns << attribute.name if attribute.prefix == 'xmlns'
       end
-      if @element.document and @element.document.doctype
+      if @element.document and (doctype = @element.document&.doctype)
         expn = @element.expanded_name
-        expn = @element.document.doctype.name if expn.size == 0
-        @element.document.doctype.attributes_of(expn).each {
+        expn = doctype.name if expn.size == 0
+        doctype.attributes_of(expn).each {
           |attribute|
           ns << attribute.name if attribute.prefix == 'xmlns'
         }
@@ -2434,10 +2433,10 @@ def 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
+      if @element.document and (doctype = @element.document&.doctype)
         expn = @element.expanded_name
-        expn = @element.document.doctype.name if expn.size == 0
-        @element.document.doctype.attributes_of(expn).each {
+        expn = doctype.name if expn.size == 0
+        doctype.attributes_of(expn).each {
           |attribute|
           namespaces[attribute.name] = attribute.value if attribute.prefix == 'xmlns' or attribute.name == 'xmlns'
         }
diff --git a/lib/rexml/text.rb b/lib/rexml/text.rb
index 6f821472..1e98aec4 100644
--- a/lib/rexml/text.rb
+++ b/lib/rexml/text.rb
@@ -201,8 +201,7 @@ def <=>( other )
 
     def doctype
       if @parent
-        doc = @parent.document
-        doc.doctype if doc
+        @parent.document&.doctype
       end
     end
 
diff --git a/lib/rexml/xpath.rb b/lib/rexml/xpath.rb
index 666d764f..db09b6e1 100644
--- a/lib/rexml/xpath.rb
+++ b/lib/rexml/xpath.rb
@@ -31,11 +31,7 @@ class XPath
     def XPath::first(element, path=nil, namespaces=nil, variables={}, options={})
       raise "The namespaces argument, if supplied, must be a hash object." unless namespaces.nil? or namespaces.kind_of?(Hash)
       raise "The variables argument, if supplied, must be a hash object." unless variables.kind_of?(Hash)
-      parser = XPathParser.new(**options)
-      parser.namespaces = namespaces
-      parser.variables = variables
-      path = "*" unless path
-      parser.parse(path, element).flatten[0]
+      match(element, path, namespaces, variables, options).flatten[0]
     end
 
     # Iterates over nodes that match the given path, calling the supplied
@@ -59,11 +55,7 @@ def XPath::first(element, path=nil, namespaces=nil, variables={}, options={})
     def XPath::each(element, path=nil, namespaces=nil, variables={}, options={}, &block)
       raise "The namespaces argument, if supplied, must be a hash object." unless namespaces.nil? or namespaces.kind_of?(Hash)
       raise "The variables argument, if supplied, must be a hash object." unless variables.kind_of?(Hash)
-      parser = XPathParser.new(**options)
-      parser.namespaces = namespaces
-      parser.variables = variables
-      path = "*" unless path
-      parser.parse(path, element).each( &block )
+      match(element, path, namespaces, variables, options).each( &block )
     end
 
     # Returns an array of nodes matching a given XPath.
@@ -72,7 +64,7 @@ def XPath::match(element, path=nil, namespaces=nil, variables={}, options={})
       parser.namespaces = namespaces
       parser.variables = variables
       path = "*" unless path
-      parser.parse(path,element)
+      parser.parse(path,element) || []
     end
   end
 end
diff --git a/lib/rexml/xpath_parser.rb b/lib/rexml/xpath_parser.rb
index 70ae8919..f03fa3c9 100644
--- a/lib/rexml/xpath_parser.rb
+++ b/lib/rexml/xpath_parser.rb
@@ -84,7 +84,7 @@ def parse path, node
         node = node.first
       end
 
-      node.document.__send__(:enable_cache) do
+      node.document&.__send__(:enable_cache) do
         match( path_stack, node )
       end
     end