Why do I get a `syntax error, unexpected tCONSTANT, expecting keyword_end`?

Question

I want to check the price of a certain product on a certain webshop.

I'm using a constant to store a Hash of webshop data so editing is easier (more stores will be added).

Here's the code I'm using:

require 'httparty'
require 'nokogiri'

class Prijscheckr

  STORES = {
    :zara => {
      'base_uri' => 'http://www.zara.com/nl/',
      'normal_price_css' => 'p.price > span',
      'css_normal_price_extract' => "[0].attr('data-price')",
      'normal_price_xpath' => '/p[3]/span',
      'xpath_normal_price_extract' => "[0].attr('data-price')"
    }
  }

  def begin(args = {})
    page = Nokogiri::HTML(HTTParty.get(args[:url]))

    price = page.css(STORES[:zara]['normal_price_css'])STORES[:zara]['css_normal_price_extract']
  end
end

When doing

p = Prijscheckr.new

p.begin(url: 'http://www.zara.com/nl/nl/collectie-aw14/dames/jacks/leren-bikerjack-c269184p2137577.html')

Here are the results:

    # Works
    # price = page.css('p.price > span')[0].attr('data-price')

    # Works
    # price = page.css(STORES[:zara]['normal_price_css'])[0].attr('data-price')

    # Does not work
    # price = page.css(STORES[:zara]['normal_price_css'])STORES[:zara]['css_normal_price_extract']

How can I concatenate price = page.css(STORES[:zara]['normal_price_css'])STORES[:zara]['css_normal_price_extract'] without hard coding it in the method?

Answer 1

Ruby code cannot be created by concatenation of string. You might like to declare css_normal_price_extract as a lamba

'css_normal_price_extract' => ->(val) {val[0].attr('data-price')}

price = STORES[:zara]['css_normal_price_extract'].call(page.css(STORES[:zara]['normal_price_css']))