Allow Liquid Tag Blocks to Span Paragraphs

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1

How do you create liquid tag blocks that can span multiple paragraphs of text? Whenever I try I receive errors like:

"Liquid Exception: Liquid syntax error (line 11): 'foo' tag was never closed in /some/path"
2

Could you post your code here?

3 
require "jekyll-pullquote/version"
require "jekyll-pullquote/utils"

module Jekyll
  class PullQuote < Liquid::Block
    def initialize(tag_name, markup, tokens)
      @markup = markup
      super
    end

    def render(context)
      output = super
      quotemarks = /\{"\s+(.+?)\s+"\}/m
      if output =~ quotemarks

        # Mute the pullquote selection tag in the original text
        output.gsub!(quotemarks, '\1')

        # Capture the pullquote selection
        quote = $1

        # Capture any desired classes
        classnames = @markup.sub(/pullquote/i, '').strip

        output = "<span class='pullquote #{classnames}' data-pullquote='#{quote}'></span>#{output}"

      else
        raise "PullQuote Error: Surround your pullquote like this {\" text to be quoted \"}"
      end
    end
  end
end

Liquid::Template.register_tag('pullquote', Jekyll::PullQuote)