Class: Builder::XmlBase
- Inherits:
-
BlankSlate
- Object
- BlankSlate
- Builder::XmlBase
- Defined in:
- lib/active_support/vendor/builder-2.1.2/builder/xmlbase.rb
Overview
XmlBase is a base class for building XML builders. See Builder::XmlMarkup and Builder::XmlEvents for examples.
Direct Known Subclasses
Instance Method Summary collapse
-
#<<(text) ⇒ Object
Append text to the output target without escaping any markup.
-
#initialize(indent = 0, initial = 0) ⇒ XmlBase
constructor
Create an XML markup builder.
-
#method_missing(sym, *args, &block) ⇒ Object
Create XML markup based on the name of the method.
-
#nil? ⇒ Boolean
For some reason, nil? is sent to the XmlMarkup object.
-
#tag!(sym, *args, &block) ⇒ Object
Create a tag named
sym
. -
#text!(text) ⇒ Object
Append text to the output target.
Methods inherited from BlankSlate
find_hidden_method, hide, reveal
Constructor Details
#initialize(indent = 0, initial = 0) ⇒ XmlBase
Create an XML markup builder.
- out
-
Object receiving the markup.
out
must respond to<<
. - indent
-
Number of spaces used for indentation (0 implies no indentation and no line breaks).
- initial
-
Level of initial indentation.
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# File 'lib/active_support/vendor/builder-2.1.2/builder/xmlbase.rb', line 22 def initialize(indent=0, initial=0) @indent = indent @level = initial end |
Dynamic Method Handling
This class handles dynamic methods through the method_missing method
#method_missing(sym, *args, &block) ⇒ Object
Create XML markup based on the name of the method. This method is never invoked directly, but is called for each markup method in the markup block.
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# File 'lib/active_support/vendor/builder-2.1.2/builder/xmlbase.rb', line 37 def method_missing(sym, *args, &block) text = nil attrs = nil sym = "#{sym}:#{args.shift}" if args.first.kind_of?(Symbol) args.each do |arg| case arg when Hash attrs ||= {} attrs.merge!(arg) else text ||= '' text << arg.to_s end end if block unless text.nil? raise ArgumentError, "XmlMarkup cannot mix a text argument with a block" end _indent _start_tag(sym, attrs) _newline _nested_structures(block) _indent _end_tag(sym) _newline elsif text.nil? _indent _start_tag(sym, attrs, true) _newline else _indent _start_tag(sym, attrs) text! text _end_tag(sym) _newline end @target end |
Instance Method Details
#<<(text) ⇒ Object
Append text to the output target without escaping any markup. May be used within the markup brackets as:
builder.p { |x| x << "<br/>HI" } #=> <p><br/>HI</p>
This is useful when using non-builder enabled software that generates strings. Just insert the string directly into the builder without changing the inserted markup.
It is also useful for stacking builder objects. Builders only use <<
to append to the target, so by supporting this method/operation builders can use other builders as their targets.
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# File 'lib/active_support/vendor/builder-2.1.2/builder/xmlbase.rb', line 97 def <<(text) _text(text) end |
#nil? ⇒ Boolean
For some reason, nil? is sent to the XmlMarkup object. If nil? is not defined and method_missing is invoked, some strange kind of recursion happens. Since nil? won’t ever be an XML tag, it is pretty safe to define it here. (Note: this is an example of cargo cult programming, cf. fishbowl.pastiche.org/2004/10/13/cargo_cult_programming).
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# File 'lib/active_support/vendor/builder-2.1.2/builder/xmlbase.rb', line 107 def nil? false end |
#tag!(sym, *args, &block) ⇒ Object
Create a tag named sym
. Other than the first argument which is the tag name, the arguments are the same as the tags implemented via method_missing
.
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# File 'lib/active_support/vendor/builder-2.1.2/builder/xmlbase.rb', line 30 def tag!(sym, *args, &block) method_missing(sym.to_sym, *args, &block) end |
#text!(text) ⇒ Object
Append text to the output target. Escape any markup. May be used within the markup brackets as:
builder.p { |b| b.br; b.text! "HI" } #=> <p><br/>HI</p>
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# File 'lib/active_support/vendor/builder-2.1.2/builder/xmlbase.rb', line 80 def text!(text) _text(_escape(text)) end |