website/libs/handlebars.dev.js
function(partial, name, context, helpers, partials, data) {
				var result = env.VM.invokePartial.apply(this, arguments);
				if (result != null) { return result; }

				if (env.compile) {
					var options = { helpers: helpers, partials: partials, data: data };
					partials[name] = env.compile(partial, { data: data !== undefined }, env);
					return partials[name](context, options);
				} else {
					throw new Exception("The partial " + name + " could not be compiled when running in runtime-only mode");
				}
			}
function(partial, name, context, helpers, partials, data) {
				var result = env.VM.invokePartial.apply(this, arguments);
				if (result != null) { return result; }

				if (env.compile) {
					var options = { helpers: helpers, partials: partials, data: data };
					partials[name] = env.compile(partial, { data: data !== undefined }, env);
					return partials[name](context, options);
				} else {
					throw new Exception("The partial " + name + " could not be compiled when running in runtime-only mode");
				}
			}
Note: Using env.VM references rather than local var references throughout this section to allow for external users to override these as psuedo-supported APIs.