// Assumes jQuery
 
var handlebarsTemplates = {};


$(function(){

  // Compile all templates
  $('script[type="text/x-handlebars-template"]').each(function(index, element) {
    var $element = $(element),
        partialName = $element.attr('data-register-partial-as');
    self.handlebarsTemplates[element.id] = Handlebars.compile($element.html());
    if (partialName) {
      Handlebars.registerPartial(partialName, $element.html());
    }
  });
  
  // Use
  var data = {};
  var html = handlebarsTemplates['my-template'](data);  

});