es5-lit-html/lib/template-factory.js

An ES5 transpiled version of lit-html

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.templateFactory = templateFactory;
exports.templateCaches = void 0;

var _template = require("./template.js");

/**
 * @license
 * Copyright (c) 2017 The Polymer Project Authors. All rights reserved.
 * This code may only be used under the BSD style license found at
 * http://polymer.github.io/LICENSE.txt
 * The complete set of authors may be found at
 * http://polymer.github.io/AUTHORS.txt
 * The complete set of contributors may be found at
 * http://polymer.github.io/CONTRIBUTORS.txt
 * Code distributed by Google as part of the polymer project is also
 * subject to an additional IP rights grant found at
 * http://polymer.github.io/PATENTS.txt
 */

/**
 * The default TemplateFactory which caches Templates keyed on
 * result.type and result.strings.
 */
function templateFactory(result) {
  var templateCache = templateCaches.get(result.type);

  if (templateCache === undefined) {
    templateCache = {
      stringsArray: new WeakMap(),
      keyString: new Map()
    };
    templateCaches.set(result.type, templateCache);
  }

  var template = templateCache.stringsArray.get(result.strings);

  if (template !== undefined) {
    return template;
  } // If the TemplateStringsArray is new, generate a key from the strings
  // This key is shared between all templates with identical content


  var key = result.strings.join(_template.marker); // Check if we already have a Template for this key

  template = templateCache.keyString.get(key);

  if (template === undefined) {
    // If we have not seen this key before, create a new Template
    template = new _template.Template(result, result.getTemplateElement()); // Cache the Template for this key

    templateCache.keyString.set(key, template);
  } // Cache all future queries for this TemplateStringsArray


  templateCache.stringsArray.set(result.strings, template);
  return template;
}

var templateCaches = new Map();
exports.templateCaches = templateCaches;