module Roda::RodaPlugins::ViewOptions::InstanceMethods

def append_view_subdir(v)

view subdirectory.
the view subdirectory to a subdirectory of the existing
If there has already been a view subdirectory set, this sets
been a view subdirectory set, this just sets it to the argument.
Append a view subdirectory to use. If there hasn't already 
def append_view_subdir(v)
  if subdir = @_view_subdir
    set_view_subdir("#{subdir}/#{v}")
  else
    set_view_subdir(v)
  end
end

def parse_template_opts(template, opts)

and locals into the returned hash.
template isn't a layout template, merge the options
If view options or locals have been set and this 
def parse_template_opts(template, opts)
  t_opts = super
  unless t_opts[:_is_layout]
    if v_opts = @_view_options
      t_opts.merge!(v_opts)
    end
    if v_locals = @_view_locals
      t_opts[:locals] = if t_locals = t_opts[:locals]
        v_locals.merge(t_locals)
      else
        v_locals
      end
    end
  end
  t_opts
end

def render_layout_opts

merge the options and locals into the returned hash.
If layout options or locals have been set, 
def render_layout_opts
  opts = super
  if l_opts = @_layout_options
    opts.merge!(l_opts)
  end
  if l_locals = @_layout_locals
    opts[:locals] = if o_locals = opts[:locals]
      o_locals.merge(l_locals)
    else
      l_locals
    end
  end
  opts
end

def set_view_subdir(v)

to not use a view subdirectory.
Set the view subdirectory to use. This can be set to nil 
def set_view_subdir(v)
  @_view_subdir = v
end

def template_name(opts)

contain a slash.
there is a view subdirectory and the template name does not
Override the template name to use the view subdirectory if the 
def template_name(opts)
  name = super
  if (v = @_view_subdir) && name !~ /\//
    "#{v}/#{name}"
  else
    name
  end
end