Build and parse URL query params with URI::Params

require "uri"

query = URI::Params.build do |form|
  form.add("q", "crystal lang")
  form.add("page", "2")
  form.add("tag", "a&b")
end

url = "https://example.com/search?#{query}"
params = URI.parse(url).query_params
puts url
puts params["q"]?              # crystal lang
puts params.fetch_all("tag")   # ["a&b"]