class Markaby::Builder

The Markaby::Builder class is the central gear in the system. When using from Ruby code, this is the only class you need to instantiate directly.

mab = Markaby::Builder.new
mab.html do
  head { title "Boats.com" }
  body do
    h1 "Boats.com has great deals"
    ul do
      li "$49 for a canoe"
      li "$39 for a raft"
      li "$29 for a huge boot that floats and can fit 5 people"
    end
  end
end
puts mab.to_s

Constants

DEFAULT_OPTIONS

Attributes

output_helpers[RW]
tagset[RW]

Public Class Methods

get(option) click to toggle source
# File lib/markaby/builder.rb, line 51
def self.get(option)
  @@options[option]
end
ignore_helpers(*helpers) click to toggle source
# File lib/markaby/builder.rb, line 59
def self.ignore_helpers(*helpers)
  ignored_helpers.concat helpers
end
ignored_helpers() click to toggle source
# File lib/markaby/builder.rb, line 55
def self.ignored_helpers
  @@ignored_helpers ||= []
end
new(assigns = {}, helper = nil, &block) click to toggle source

Create a Markaby builder object. Pass in a hash of variable assignments to assigns which will be available as instance variables inside tag construction blocks. If an object is passed in to helper, its methods will be available from those same blocks.

Pass in a block to new and the block will be evaluated.

mab = Markaby::Builder.new {
  html do
    body do
      h1 "Matching Mole"
    end
  end
}
# File lib/markaby/builder.rb, line 80
def initialize(assigns = {}, helper = nil, &block)
  @streams = [Stream.new]
  @assigns = assigns.dup
  @_helper = helper
  @used_ids = {}

  @@options.each do |k, v|
    instance_variable_set("@#{k}", @assigns.delete(k) || v)
  end

  @assigns.each do |k, v|
    instance_variable_set("@#{k}", v)
  end

  if helper
    helper.instance_variables.each do |iv|
      instance_variable_set(iv, helper.instance_variable_get(iv))
    end
  end

  @builder = XmlMarkup.new(:indent => @indent, :target => @streams.last)

  text(capture(&block)) if block
end
restore_defaults!() click to toggle source
# File lib/markaby/builder.rb, line 43
def self.restore_defaults!
  @@options = DEFAULT_OPTIONS.dup
end
set(option, value) click to toggle source
# File lib/markaby/builder.rb, line 47
def self.set(option, value)
  @@options[option] = value
end

Public Instance Methods

<<(string)
Alias for: text
capture(&block) click to toggle source

Captures the HTML code built inside the block. This is done by creating a new stream for the builder object, running the block and passing back its stream as a string.

>> Markaby::Builder.new.capture { h1 "TEST"; h2 "CAPTURE ME" }
=> "<h1>TEST</h1><h2>CAPTURE ME</h2>"
# File lib/markaby/builder.rb, line 145
def capture(&block)
  @streams.push(@builder.target = Stream.new)
  @builder.level += 1
  str = instance_eval(&block)
  str = @streams.last.join if @streams.last.any?
  @streams.pop
  @builder.level -= 1
  @builder.target = @streams.last
  str
end
concat(string)
Alias for: text
helper=(helper) click to toggle source
# File lib/markaby/builder.rb, line 105
def helper=(helper)
  @_helper = helper
end
locals=(locals) click to toggle source
# File lib/markaby/builder.rb, line 116
def locals=(locals)
  locals.each do |key, value|
    metaclass do
      define_method key do
        value
      end
    end
  end
end
tag!(tag, *args, &block) click to toggle source

Create a tag named tag. Other than the first argument which is the tag name, the arguments are the same as the tags implemented via method_missing.

# File lib/markaby/builder.rb, line 158
def tag!(tag, *args, &block)
  ele_id = nil
  if @auto_validation && @tagset
    if !@tagset.tagset.has_key?(tag)
      raise InvalidXhtmlError, "no element `#{tag}' for #{tagset.doctype}"
    elsif args.last.respond_to?(:to_hash)
      attrs = args.last.to_hash

      if @tagset.forms.include?(tag) && attrs[:id]
        attrs[:name] ||= attrs[:id]
      end

      attrs.each do |k, v|
        atname = k.to_s.downcase.intern
        unless k =~ /:/ or @tagset.tagset[tag].include? atname
          raise InvalidXhtmlError, "no attribute `#{k}' on #{tag} elements"
        end
        if atname == :id
          ele_id = v.to_s
          if @used_ids.has_key? ele_id
            raise InvalidXhtmlError, "id `#{ele_id}' already used (id's must be unique)."
          end
        end
        if AttrsBoolean.include? atname
          if v
            attrs[k] = atname.to_s
          else
            attrs.delete k
          end
        end
      end
    end
  end

  if block
    str = capture(&block)
    block = proc { text(str) }
  end

  f = fragment { @builder.tag!(tag, *args, &block) }
  @used_ids[ele_id] = f if ele_id
  f
end
text(string) click to toggle source

Write a string to the HTML stream without escaping it.

# File lib/markaby/builder.rb, line 132
def text(string)
  @builder << string.to_s
  nil
end
Also aliased as: <<, concat
to_s() click to toggle source

Returns a string containing the HTML stream. Internally, the stream is stored as an Array.

# File lib/markaby/builder.rb, line 127
def to_s
  @streams.last.to_s
end

Private Instance Methods

fragment() { || ... } click to toggle source
# File lib/markaby/builder.rb, line 262
def fragment
  stream = @streams.last
  start = stream.length
  yield
  length = stream.length - start
  Fragment.new(stream, start, length)
end
instance_methods_for(obj) click to toggle source
# File lib/markaby/builder.rb, line 249
def instance_methods_for(obj)
  obj.instance_methods
end
instance_variables_for(obj) click to toggle source
# File lib/markaby/builder.rb, line 245
def instance_variables_for(obj)
  obj.instance_variables
end
metaclass(&block) click to toggle source
# File lib/markaby/builder.rb, line 109
def metaclass(&block)
  metaclass = class << self; self; end
  metaclass.class_eval(&block)
end
method_missing(sym, *args, &block) click to toggle source

This method is used to intercept calls to helper methods and instance variables. Here is the order of interception:

  • If sym is a helper method, the helper method is called and output to the stream.

  • If sym is a Builder::XmlMarkup method, it is passed on to the builder object.

  • If sym is also the name of an instance variable, the value of the instance variable is returned.

  • If sym has come this far and no tagset is found, sym and its arguments are passed to tag!

  • If a tagset is found, though, NoMethodError is raised.

#method_missing used to be the lynchpin in Markaby, but it's no longer used to handle HTML tags. See html_tag for that.

Calls superclass method
# File lib/markaby/builder.rb, line 217
def method_missing(sym, *args, &block)
  if @_helper.respond_to?(sym, true) && !self.class.ignored_helpers.include?(sym)
    r = @_helper.send(sym, *args, &block)
    if @output_helpers && r.respond_to?(:to_str)
      fragment { @builder << r }
    else
      r
    end
  elsif @assigns.has_key?(sym)
    @assigns[sym]
  elsif @assigns.has_key?(stringy_key = sym.to_s)
    # Rails' ActionView assigns hash has string keys for
    # instance variables that are defined in the controller.
    @assigns[stringy_key]
  elsif instance_variables_for(self).include?(ivar = "@#{sym}".to_sym)
    instance_variable_get(ivar)
  elsif @_helper && instance_variables_for(@_helper).include?(ivar)
    @_helper.instance_variable_get(ivar)
  elsif instance_methods_for(::Builder::XmlMarkup).include?(sym)
    @builder.__send__(sym, *args, &block)
  elsif !@tagset
    tag!(sym, *args, &block)
  else
    super
  end
end