Push Javascript functionality to static files called with dynamic parameters

application.js

// put the view editing Javascript logic in a static .js file:

MyApp = {
  onCreateReview: function(flash, newReviewsCount, reviewPartial) {
    $("#new_review").before('<div id="flash_notice">' + flash + '</div>');
    $("#reviews_count").html(newReviewsCount);
    $("#reviews").append(reviewPartial);
    $("#new_review")[0].reset();
  }
};

much_better.js.erb

// views/reviews/create.js.erb
// from http://railscasts.com/episodes/136-jquery
MyApp.onCreateReview(
  "<%= escape_javascriptflash.delete(:notice)) -%>",
  "<%= pluralize(@review.product.reviews.count, 'Review') %>",
  "<%= escape_javascript(render(:partial => @review)) -%>");

too_much_dynamic.js.erb

// views/reviews/create.js.erb
// from http://railscasts.com/episodes/136-jquery
/* This puts too much logic in a dynamic view. That makes it
   hard to unit test. Instead, change this to the
   much_better.js.erb version and add the above code
   to application.js
 */
$("#new_review").before('<div id="flash_notice"><%= escape_javascript(flash.delete(:notice)) %></div>');
$("#reviews_count").html("<%= pluralize(@review.product.reviews.count, 'Review') %>");
$("#reviews").append("<%= escape_javascript(render(:partial => @review)) %>");
$("#new_review")[0].reset();