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requirejs--源码分析
1 /*---------------------------------------start-------------------------------*/ 2 req({}); // num == 1 跳到 num == 2 3 4 //Exports some context-sensitive methods on global require. 5 each([ 6 ‘toUrl‘, 7 ‘undef‘, 8 ‘defined‘, 9 ‘specified‘ 10 ], function (prop) { 11 //Reference from contexts instead of early binding to default context, 12 //so that during builds, the latest instance of the default context 13 //with its config gets used. 14 req[prop] = function () { 15 var ctx = contexts[defContextName]; 16 return ctx.require[prop].apply(ctx, arguments); 17 }; 18 }); 19 20 if (isBrowser && !cfg.skipDataMain) {} //req.deps[mainscript] 21 22 23 //Set up with config info. 24 req(cfg); //最后启动。 按照之前写的num 一步一步的去加载。 25 26 /*----------------------------------------start---------------------------------*/ 27 //第一次 num == 2 28 //params 29 30 var deps = {}, 31 callback = undefined, 32 errback = undefined, 33 optional = undefined; 34 35 36 //--------------声明------------------ 37 var context = undefined, 38 config = undefined, 39 contextName = defContextName; 40 41 //-------------判断--------------- 42 43 config = {}; 44 deps = []; 45 46 //------------判断-------------- 47 context = contexts[contextName] = req.s.newContext(contextName); //跳到num ==3 48 49 //时间上就是执行 localRequire(deps, callback, errback); 50 context.require(deps, callback, errback); //跳到 num ==5 51 52 53 /*---------------------------------------end-------------------------------*/ 54 /* 55 * 56 * 57 * */ 58 /*---------------------------------------start-------------------------------*/ 59 //-----------------------进入核心函数-------------------------- 60 //第一次 61 //function newContext(contextName) num == 3 62 context = { 63 config: config, 64 contextName: contextName, 65 registry: registry, 66 defined: defined, 67 urlFetched: urlFetched, 68 defQueue: defQueue, 69 defQueueMap: {}, 70 Module: Module, 71 makeModuleMap: makeModuleMap, 72 nextTick: req.nextTick, 73 one rror: one rror, 74 75 /** 76 * Set a configuration for the context. 77 * @param {Object} cfg config object to integrate. 78 */ 79 configure: function (cfg) { 80 //Make sure the baseUrl ends in a slash. 81 if (cfg.baseUrl) { 82 if (cfg.baseUrl.charAt(cfg.baseUrl.length - 1) !== ‘/‘) { 83 cfg.baseUrl += ‘/‘; 84 } 85 } 86 87 // Convert old style urlArgs string to a function. 88 if (typeof cfg.urlArgs === ‘string‘) { 89 var urlArgs = cfg.urlArgs; 90 cfg.urlArgs = function(id, url) { 91 return (url.indexOf(‘?‘) === -1 ? ‘?‘ : ‘&‘) + urlArgs; 92 }; 93 } 94 95 //Save off the paths since they require special processing, 96 //they are additive. 97 var shim = config.shim, 98 objs = { 99 paths: true, 100 bundles: true, 101 config: true, 102 map: true 103 }; 104 105 eachProp(cfg, function (value, prop) { 106 if (objs[prop]) { 107 if (!config[prop]) { 108 config[prop] = {}; 109 } 110 mixin(config[prop], value, true, true); 111 } else { 112 config[prop] = value; 113 } 114 }); 115 116 //Reverse map the bundles 117 if (cfg.bundles) { 118 eachProp(cfg.bundles, function (value, prop) { 119 each(value, function (v) { 120 if (v !== prop) { 121 bundlesMap[v] = prop; 122 } 123 }); 124 }); 125 } 126 127 //Merge shim 128 if (cfg.shim) { 129 eachProp(cfg.shim, function (value, id) { 130 //Normalize the structure 131 if (isArray(value)) { 132 value =http://www.mamicode.com/ { 133 deps: value 134 }; 135 } 136 if ((value.exports || value.init) && !value.exportsFn) { 137 value.exportsFn = context.makeShimExports(value); 138 } 139 shim[id] = value; 140 }); 141 config.shim = shim; 142 } 143 144 //Adjust packages if necessary. 145 if (cfg.packages) { 146 each(cfg.packages, function (pkgObj) { 147 var location, name; 148 149 pkgObj = typeof pkgObj === ‘string‘ ? {name: pkgObj} : pkgObj; 150 151 name = pkgObj.name; 152 location = pkgObj.location; 153 if (location) { 154 config.paths[name] = pkgObj.location; 155 } 156 157 //Save pointer to main module ID for pkg name. 158 //Remove leading dot in main, so main paths are normalized, 159 //and remove any trailing .js, since different package 160 //envs have different conventions: some use a module name, 161 //some use a file name. 162 config.pkgs[name] = pkgObj.name + ‘/‘ + (pkgObj.main || ‘main‘) 163 .replace(currDirRegExp, ‘‘) 164 .replace(jsSuffixRegExp, ‘‘); 165 }); 166 } 167 168 //If there are any "waiting to execute" modules in the registry, 169 //update the maps for them, since their info, like URLs to load, 170 //may have changed. 171 eachProp(registry, function (mod, id) { 172 //If module already has init called, since it is too 173 //late to modify them, and ignore unnormalized ones 174 //since they are transient. 175 if (!mod.inited && !mod.map.unnormalized) { 176 mod.map = makeModuleMap(id, null, true); 177 } 178 }); 179 180 //If a deps array or a config callback is specified, then call 181 //require with those args. This is useful when require is defined as a 182 //config object before require.js is loaded. 183 if (cfg.deps || cfg.callback) { 184 context.require(cfg.deps || [], cfg.callback); 185 } 186 }, 187 188 makeShimExports: function (value) { 189 function fn() { 190 var ret; 191 if (value.init) { 192 ret = value.init.apply(global, arguments); 193 } 194 return ret || (value.exports && getGlobal(value.exports)); 195 } 196 return fn; 197 }, 198 199 makeRequire: function (relMap, options) { 200 options = options || {}; 201 202 function localRequire(deps, callback, errback) { 203 var id, map, requireMod; 204 205 if (options.enableBuildCallback && callback && isFunction(callback)) { 206 callback.__requireJsBuild = true; 207 } 208 209 if (typeof deps === ‘string‘) { 210 if (isFunction(callback)) { 211 //Invalid call 212 return one rror(makeError(‘requireargs‘, ‘Invalid require call‘), errback); 213 } 214 215 //If require|exports|module are requested, get the 216 //value for them from the special handlers. Caveat: 217 //this only works while module is being defined. 218 if (relMap && hasProp(handlers, deps)) { 219 return handlers[deps](registry[relMap.id]); 220 } 221 222 //Synchronous access to one module. If require.get is 223 //available (as in the Node adapter), prefer that. 224 if (req.get) { 225 return req.get(context, deps, relMap, localRequire); 226 } 227 228 //Normalize module name, if it contains . or .. 229 map = makeModuleMap(deps, relMap, false, true); 230 id = map.id; 231 232 if (!hasProp(defined, id)) { 233 return one rror(makeError(‘notloaded‘, ‘Module name "‘ + 234 id + 235 ‘" has not been loaded yet for context: ‘ + 236 contextName + 237 (relMap ? ‘‘ : ‘. Use require([])‘))); 238 } 239 return defined[id]; 240 } 241 242 //Grab defines waiting in the global queue. 243 intakeDefines(); 244 245 //Mark all the dependencies as needing to be loaded. 246 context.nextTick(function () { 247 //Some defines could have been added since the 248 //require call, collect them. 249 intakeDefines(); 250 251 requireMod = getModule(makeModuleMap(null, relMap)); 252 253 //Store if map config should be applied to this require 254 //call for dependencies. 255 requireMod.skipMap = options.skipMap; 256 257 requireMod.init(deps, callback, errback, { 258 enabled: true 259 }); 260 261 checkLoaded(); 262 }); 263 264 return localRequire; 265 } 266 267 mixin(localRequire, { 268 isBrowser: isBrowser, 269 270 /** 271 * Converts a module name + .extension into an URL path. 272 * *Requires* the use of a module name. It does not support using 273 * plain URLs like nameToUrl. 274 */ 275 toUrl: function (moduleNamePlusExt) { 276 var ext, 277 index = moduleNamePlusExt.lastIndexOf(‘.‘), 278 segment = moduleNamePlusExt.split(‘/‘)[0], 279 isRelative = segment === ‘.‘ || segment === ‘..‘; 280 281 //Have a file extension alias, and it is not the 282 //dots from a relative path. 283 if (index !== -1 && (!isRelative || index > 1)) { 284 ext = moduleNamePlusExt.substring(index, moduleNamePlusExt.length); 285 moduleNamePlusExt = moduleNamePlusExt.substring(0, index); 286 } 287 288 return context.nameToUrl(normalize(moduleNamePlusExt, 289 relMap && relMap.id, true), ext, true); 290 }, 291 292 defined: function (id) { 293 return hasProp(defined, makeModuleMap(id, relMap, false, true).id); 294 }, 295 296 specified: function (id) { 297 id = makeModuleMap(id, relMap, false, true).id; 298 return hasProp(defined, id) || hasProp(registry, id); 299 } 300 }); 301 302 //Only allow undef on top level require calls 303 if (!relMap) { 304 localRequire.undef = function (id) { 305 //Bind any waiting define() calls to this context, 306 //fix for #408 307 takeGlobalQueue(); 308 309 var map = makeModuleMap(id, relMap, true), 310 mod = getOwn(registry, id); 311 312 mod.undefed = true; 313 removeScript(id); 314 315 delete defined[id]; 316 delete urlFetched[map.url]; 317 delete undefEvents[id]; 318 319 //Clean queued defines too. Go backwards 320 //in array so that the splices do not 321 //mess up the iteration. 322 eachReverse(defQueue, function(args, i) { 323 if (args[0] === id) { 324 defQueue.splice(i, 1); 325 } 326 }); 327 delete context.defQueueMap[id]; 328 329 if (mod) { 330 //Hold on to listeners in case the 331 //module will be attempted to be reloaded 332 //using a different config. 333 if (mod.events.defined) { 334 undefEvents[id] = mod.events; 335 } 336 337 cleanRegistry(id); 338 } 339 }; 340 } 341 342 return localRequire; 343 }, 344 345 /** 346 * Called to enable a module if it is still in the registry 347 * awaiting enablement. A second arg, parent, the parent module, 348 * is passed in for context, when this method is overridden by 349 * the optimizer. Not shown here to keep code compact. 350 */ 351 enable: function (depMap) { 352 var mod = getOwn(registry, depMap.id); 353 if (mod) { 354 getModule(depMap).enable(); 355 } 356 }, 357 358 /** 359 * Internal method used by environment adapters to complete a load event. 360 * A load event could be a script load or just a load pass from a synchronous 361 * load call. 362 * @param {String} moduleName the name of the module to potentially complete. 363 */ 364 completeLoad: function (moduleName) { 365 var found, args, mod, 366 shim = getOwn(config.shim, moduleName) || {}, 367 shExports = shim.exports; 368 369 takeGlobalQueue(); 370 371 while (defQueue.length) { 372 args = defQueue.shift(); 373 if (args[0] === null) { 374 args[0] = moduleName; 375 //If already found an anonymous module and bound it 376 //to this name, then this is some other anon module 377 //waiting for its completeLoad to fire. 378 if (found) { 379 break; 380 } 381 found = true; 382 } else if (args[0] === moduleName) { 383 //Found matching define call for this script! 384 found = true; 385 } 386 387 callGetModule(args); 388 } 389 context.defQueueMap = {}; 390 391 //Do this after the cycle of callGetModule in case the result 392 //of those calls/init calls changes the registry. 393 mod = getOwn(registry, moduleName); 394 395 if (!found && !hasProp(defined, moduleName) && mod && !mod.inited) { 396 if (config.enforceDefine && (!shExports || !getGlobal(shExports))) { 397 if (hasPathFallback(moduleName)) { 398 return; 399 } else { 400 return one rror(makeError(‘nodefine‘, 401 ‘No define call for ‘ + moduleName, 402 null, 403 [moduleName])); 404 } 405 } else { 406 //A script that does not call define(), so just simulate 407 //the call for it. 408 callGetModule([moduleName, (shim.deps || []), shim.exportsFn]); 409 } 410 } 411 412 checkLoaded(); 413 }, 414 415 /** 416 * Converts a module name to a file path. Supports cases where 417 * moduleName may actually be just an URL. 418 * Note that it **does not** call normalize on the moduleName, 419 * it is assumed to have already been normalized. This is an 420 * internal API, not a public one. Use toUrl for the public API. 421 */ 422 nameToUrl: function (moduleName, ext, skipExt) { 423 var paths, syms, i, parentModule, url, 424 parentPath, bundleId, 425 pkgMain = getOwn(config.pkgs, moduleName); 426 427 if (pkgMain) { 428 moduleName = pkgMain; 429 } 430 431 bundleId = getOwn(bundlesMap, moduleName); 432 433 if (bundleId) { 434 return context.nameToUrl(bundleId, ext, skipExt); 435 } 436 437 //If a colon is in the URL, it indicates a protocol is used and it is just 438 //an URL to a file, or if it starts with a slash, contains a query arg (i.e. ?) 439 //or ends with .js, then assume the user meant to use an url and not a module id. 440 //The slash is important for protocol-less URLs as well as full paths. 441 if (req.jsExtRegExp.test(moduleName)) { 442 //Just a plain path, not module name lookup, so just return it. 443 //Add extension if it is included. This is a bit wonky, only non-.js things pass 444 //an extension, this method probably needs to be reworked. 445 url = moduleName + (ext || ‘‘); 446 } else { 447 //A module that needs to be converted to a path. 448 paths = config.paths; 449 450 syms = moduleName.split(‘/‘); 451 //For each module name segment, see if there is a path 452 //registered for it. Start with most specific name 453 //and work up from it. 454 for (i = syms.length; i > 0; i -= 1) { 455 parentModule = syms.slice(0, i).join(‘/‘); 456 457 parentPath = getOwn(paths, parentModule); 458 if (parentPath) { 459 //If an array, it means there are a few choices, 460 //Choose the one that is desired 461 if (isArray(parentPath)) { 462 parentPath = parentPath[0]; 463 } 464 syms.splice(0, i, parentPath); 465 break; 466 } 467 } 468 469 //Join the path parts together, then figure out if baseUrl is needed. 470 url = syms.join(‘/‘); 471 url += (ext || (/^data\:|^blob\:|\?/.test(url) || skipExt ? ‘‘ : ‘.js‘)); 472 url = (url.charAt(0) === ‘/‘ || url.match(/^[\w\+\.\-]+:/) ? ‘‘ : config.baseUrl) + url; 473 } 474 475 return config.urlArgs && !/^blob\:/.test(url) ? 476 url + config.urlArgs(moduleName, url) : url; 477 }, 478 479 //Delegates to req.load. Broken out as a separate function to 480 //allow overriding in the optimizer. 481 load: function (id, url) { 482 req.load(context, id, url); 483 }, 484 485 /** 486 * Executes a module callback function. Broken out as a separate function 487 * solely to allow the build system to sequence the files in the built 488 * layer in the right sequence. 489 * 490 * @private 491 */ 492 execCb: function (name, callback, args, exports) { 493 return callback.apply(exports, args); 494 }, 495 496 /** 497 * callback for script loads, used to check status of loading. 498 * 499 * @param {Event} evt the event from the browser for the script 500 * that was loaded. 501 */ 502 onScriptLoad: function (evt) { 503 //Using currentTarget instead of target for Firefox 2.0‘s sake. Not 504 //all old browsers will be supported, but this one was easy enough 505 //to support and still makes sense. 506 if (evt.type === ‘load‘ || 507 (readyRegExp.test((evt.currentTarget || evt.srcElement).readyState))) { 508 //Reset interactive script so a script node is not held onto for 509 //to long. 510 interactiveScript = null; 511 512 //Pull out the name of the module and the context. 513 var data =http://www.mamicode.com/ getScriptData(evt); 514 context.completeLoad(data.id); 515 } 516 }, 517 518 /** 519 * Callback for script errors. 520 */ 521 onScriptError: function (evt) { 522 var data =http://www.mamicode.com/ getScriptData(evt); 523 if (!hasPathFallback(data.id)) { 524 var parents = []; 525 eachProp(registry, function(value, key) { 526 if (key.indexOf(‘_@r‘) !== 0) { 527 each(value.depMaps, function(depMap) { 528 if (depMap.id === data.id) { 529 parents.push(key); 530 return true; 531 } 532 }); 533 } 534 }); 535 return one rror(makeError(‘scripterror‘, ‘Script error for "‘ + data.id + 536 (parents.length ? 537 ‘", needed by: ‘ + parents.join(‘, ‘) : 538 ‘"‘), evt, [data.id])); 539 } 540 } 541 }; 542 543 //得到一个闭包环境 544 context.require = context.makeRequire(); //跳到num ===4 545 546 //return context; 547 /*---------------------------------------end-------------------------------*/ 548 /* 549 * 550 * 551 * 552 * 553 * 554 * */ 555 /*---------------------------------------start-------------------------------*/ 556 //--------------------------进入makeRequire------------------------ 557 //第一次 558 //params [relMap , options] num == 4 559 560 var relMap = undefined, 561 options = {}; 562 563 564 //声明localRequire函数 565 var localRequire= function(deps, callback, errback){}; 566 567 //给localRequire加属性 568 var fn1={ 569 isBrowser: isBrowser, 570 571 /** 572 * Converts a module name + .extension into an URL path. 573 * *Requires* the use of a module name. It does not support using 574 * plain URLs like nameToUrl. 575 */ 576 toUrl: function (moduleNamePlusExt) { 577 var ext, 578 index = moduleNamePlusExt.lastIndexOf(‘.‘), 579 segment = moduleNamePlusExt.split(‘/‘)[0], 580 isRelative = segment === ‘.‘ || segment === ‘..‘; 581 582 //Have a file extension alias, and it is not the 583 //dots from a relative path. 584 if (index !== -1 && (!isRelative || index > 1)) { 585 ext = moduleNamePlusExt.substring(index, moduleNamePlusExt.length); 586 moduleNamePlusExt = moduleNamePlusExt.substring(0, index); 587 } 588 589 return context.nameToUrl(normalize(moduleNamePlusExt, 590 relMap && relMap.id, true), ext, true); 591 }, 592 593 defined: function (id) { 594 return hasProp(defined, makeModuleMap(id, relMap, false, true).id); 595 }, 596 597 specified: function (id) { 598 id = makeModuleMap(id, relMap, false, true).id; 599 return hasProp(defined, id) || hasProp(registry, id); 600 } 601 }; 602 603 604 //---------------------- 判断 if (!relMap)---------------------- 605 606 //加属性 607 608 var fn2 = undef = function(id){}; 609 610 //返回return localRequire; 611 612 //总结一下 就是返回一个函数,给他加了一些属性; 613 /*---------------------------------------end-------------------------------*/ 614 /* 615 * 616 * */ 617 618 /*---------------------------------------start-------------------------------*/ 619 // num == 5 620 intakeDefines() // 调到num == 6 621 /* 622 * while (defQueue.length) {}遍历 defQueue; 623 * 624 * 625 * 626 * */ 627 628 callGetModule(args); //args [id,deps,callb] 跳到num = 7 629 630 context.defQueueMap = {}; 631 632 context.nextTick(function () { 633 //Some defines could have been added since the 634 //require call, collect them. 635 intakeDefines(); 636 637 requireMod = getModule(makeModuleMap(null, relMap)); 638 639 //Store if map config should be applied to this require 640 //call for dependencies. 641 requireMod.skipMap = options.skipMap; 642 643 requireMod.init(deps, callback, errback, { 644 enabled: true 645 }); 646 647 checkLoaded(); 648 }); //跳转到 12 649 650 651 /*---------------------------------------end-------------------------------*/ 652 /* 653 * 654 * 655 * 656 * 657 * */ 658 /*---------------------------------------start-------------------------------*/ 659 /* function takeGlobalQueue() num == 6 660 * */ 661 662 //把globalDefQueue 里面通过define(id,desp,callback) 都放到 特定context 下的 defQueue 663 664 //并且最后清空 globalDefQueue = []; 665 666 /*---------------------------------------end-------------------------------*/ 667 /* 668 * 669 * 670 * 671 * 672 * */ 673 /*---------------------------------------start-------------------------------*/ 674 // function callGetModule(args) num == 7 675 676 //将 defined里没有的 id进行构建模块 677 if (!hasProp(defined, args[0])) { 678 getModule(makeModuleMap(args[0], null, true)).init(args[1], args[2]); 679 } 680 681 makeModuleMap(args[0], null, true) //跳转到 num== 8 682 683 getModule(makeModuleMap(args[0], null, true)) //跳转到 num == 9 684 685 getModule(makeModuleMap(args[0], null, true)).init(args[1], args[2]);//跳转到 num == 11 686 //生成的Module 里面的map属性 就是 makeModuleMap返回的对象。 687 688 689 /*---------------------------------------end-------------------------------*/ 690 /* 691 * 692 * 693 * 694 * 695 * */ 696 /*---------------------------------------start-------------------------------*/ 697 698 //function makeModuleMap(name, parentModuleMap, isNormalized, applyMap) //num == 8 699 700 //返回obj 701 var obj = { 702 prefix: prefix, 703 name: normalizedName, 704 parentMap: parentModuleMap, 705 unnormalized: !!suffix, 706 url: url, 707 originalName: originalName, 708 isDefine: isDefine, 709 id: (prefix ? 710 prefix + ‘!‘ + normalizedName : 711 normalizedName) + suffix 712 }; 713 714 /*---------------------------------------end-------------------------------*/ 715 /* 716 * 717 * 718 * 719 * 720 * */ 721 /*-----------------------------------------start--------------------------------*/ 722 723 //function getModule(depMap) num == 9 724 var id = depMap.id, 725 mod = getOwn(registry, id); 726 727 if (!mod) { 728 mod = registry[id] = new context.Module(depMap); 729 } 730 731 new context.Module(depMap); //跳转到10 732 733 //return mod; 734 735 /*----------------------------------------end-------------------------*/ 736 /* 737 * 738 * 739 * 740 * 741 * */ 742 /*-----------------------------------------start--------------------------------*/ 743 //num ===10 744 Module = function (map) { 745 this.events = getOwn(undefEvents, map.id) || {}; 746 this.map = map; 747 this.shim = getOwn(config.shim, map.id); 748 this.depExports = []; 749 this.depMaps = []; 750 this.depMatched = []; 751 this.pluginMaps = {}; 752 this.depCount = 0; 753 754 /* this.exports this.factory 755 this.depMaps = [], 756 this.enabled, this.fetched 757 */ 758 }; 759 760 Module.prototype = { 761 init: function (depMaps, factory, errback, options) { 762 options = options || {}; 763 764 //Do not do more inits if already done. Can happen if there 765 //are multiple define calls for the same module. That is not 766 //a normal, common case, but it is also not unexpected. 767 if (this.inited) { 768 return; 769 } 770 771 this.factory = factory; 772 773 if (errback) { 774 //Register for errors on this module. 775 this.on(‘error‘, errback); 776 } else if (this.events.error) { 777 //If no errback already, but there are error listeners 778 //on this module, set up an errback to pass to the deps. 779 errback = bind(this, function (err) { 780 this.emit(‘error‘, err); 781 }); 782 } 783 784 //Do a copy of the dependency array, so that 785 //source inputs are not modified. For example 786 //"shim" deps are passed in here directly, and 787 //doing a direct modification of the depMaps array 788 //would affect that config. 789 this.depMaps = depMaps && depMaps.slice(0); 790 791 this.errback = errback; 792 793 //Indicate this module has be initialized 794 this.inited = true; 795 796 this.ignore = options.ignore; 797 798 //Could have option to init this module in enabled mode, 799 //or could have been previously marked as enabled. However, 800 //the dependencies are not known until init is called. So 801 //if enabled previously, now trigger dependencies as enabled. 802 if (options.enabled || this.enabled) { 803 //Enable this module and dependencies. 804 //Will call this.check() 805 this.enable(); 806 } else { 807 this.check(); 808 } 809 }, 810 811 defineDep: function (i, depExports) { 812 //Because of cycles, defined callback for a given 813 //export can be called more than once. 814 if (!this.depMatched[i]) { 815 this.depMatched[i] = true; 816 this.depCount -= 1; 817 this.depExports[i] = depExports; 818 } 819 }, 820 821 fetch: function () { 822 if (this.fetched) { 823 return; 824 } 825 this.fetched = true; 826 827 context.startTime = (new Date()).getTime(); 828 829 var map = this.map; 830 831 //If the manager is for a plugin managed resource, 832 //ask the plugin to load it now. 833 if (this.shim) { 834 context.makeRequire(this.map, { 835 enableBuildCallback: true 836 })(this.shim.deps || [], bind(this, function () { 837 return map.prefix ? this.callPlugin() : this.load(); 838 })); 839 } else { 840 //Regular dependency. 841 return map.prefix ? this.callPlugin() : this.load(); 842 } 843 }, 844 845 load: function () { 846 var url = this.map.url; 847 848 //Regular dependency. 849 if (!urlFetched[url]) { 850 urlFetched[url] = true; 851 context.load(this.map.id, url); 852 } 853 }, 854 855 /** 856 * Checks if the module is ready to define itself, and if so, 857 * define it. 858 */ 859 check: function () { 860 if (!this.enabled || this.enabling) { 861 return; 862 } 863 864 var err, cjsModule, 865 id = this.map.id, 866 depExports = this.depExports, 867 exports = this.exports, 868 factory = this.factory; 869 870 if (!this.inited) { 871 // Only fetch if not already in the defQueue. 872 if (!hasProp(context.defQueueMap, id)) { 873 this.fetch(); 874 } 875 } else if (this.error) { 876 this.emit(‘error‘, this.error); 877 } else if (!this.defining) { 878 //The factory could trigger another require call 879 //that would result in checking this module to 880 //define itself again. If already in the process 881 //of doing that, skip this work. 882 this.defining = true; 883 884 if (this.depCount < 1 && !this.defined) { 885 if (isFunction(factory)) { 886 //If there is an error listener, favor passing 887 //to that instead of throwing an error. However, 888 //only do it for define()‘d modules. require 889 //errbacks should not be called for failures in 890 //their callbacks (#699). However if a global 891 //onError is set, use that. 892 if ((this.events.error && this.map.isDefine) || 893 req.onError !== defaultOnError) { 894 try { 895 exports = context.execCb(id, factory, depExports, exports); 896 } catch (e) { 897 err = e; 898 } 899 } else { 900 exports = context.execCb(id, factory, depExports, exports); 901 } 902 903 // Favor return value over exports. If node/cjs in play, 904 // then will not have a return value anyway. Favor 905 // module.exports assignment over exports object. 906 if (this.map.isDefine && exports === undefined) { 907 cjsModule = this.module; 908 if (cjsModule) { 909 exports = cjsModule.exports; 910 } else if (this.usingExports) { 911 //exports already set the defined value. 912 exports = this.exports; 913 } 914 } 915 916 if (err) { 917 err.requireMap = this.map; 918 err.requireModules = this.map.isDefine ? [this.map.id] : null; 919 err.requireType = this.map.isDefine ? ‘define‘ : ‘require‘; 920 return one rror((this.error = err)); 921 } 922 923 } else { 924 //Just a literal value 925 exports = factory; 926 } 927 928 this.exports = exports; 929 930 if (this.map.isDefine && !this.ignore) { 931 defined[id] = exports; 932 933 if (req.onResourceLoad) { 934 var resLoadMaps = []; 935 each(this.depMaps, function (depMap) { 936 resLoadMaps.push(depMap.normalizedMap || depMap); 937 }); 938 req.onResourceLoad(context, this.map, resLoadMaps); 939 } 940 } 941 942 //Clean up 943 cleanRegistry(id); 944 945 this.defined = true; 946 } 947 948 //Finished the define stage. Allow calling check again 949 //to allow define notifications below in the case of a 950 //cycle. 951 this.defining = false; 952 953 if (this.defined && !this.defineEmitted) { 954 this.defineEmitted = true; 955 this.emit(‘defined‘, this.exports); 956 this.defineEmitComplete = true; 957 } 958 959 } 960 }, 961 962 callPlugin: function () { 963 var map = this.map, 964 id = map.id, 965 //Map already normalized the prefix. 966 pluginMap = makeModuleMap(map.prefix); 967 968 //Mark this as a dependency for this plugin, so it 969 //can be traced for cycles. 970 this.depMaps.push(pluginMap); 971 972 on(pluginMap, ‘defined‘, bind(this, function (plugin) { 973 var load, normalizedMap, normalizedMod, 974 bundleId = getOwn(bundlesMap, this.map.id), 975 name = this.map.name, 976 parentName = this.map.parentMap ? this.map.parentMap.name : null, 977 localRequire = context.makeRequire(map.parentMap, { 978 enableBuildCallback: true 979 }); 980 981 //If current map is not normalized, wait for that 982 //normalized name to load instead of continuing. 983 if (this.map.unnormalized) { 984 //Normalize the ID if the plugin allows it. 985 if (plugin.normalize) { 986 name = plugin.normalize(name, function (name) { 987 return normalize(name, parentName, true); 988 }) || ‘‘; 989 } 990 991 //prefix and name should already be normalized, no need 992 //for applying map config again either. 993 normalizedMap = makeModuleMap(map.prefix + ‘!‘ + name, 994 this.map.parentMap); 995 on(normalizedMap, 996 ‘defined‘, bind(this, function (value) { 997 this.map.normalizedMap = normalizedMap; 998 this.init([], function () { return value; }, null, { 999 enabled: true, 1000 ignore: true 1001 }); 1002 })); 1003 1004 normalizedMod = getOwn(registry, normalizedMap.id); 1005 if (normalizedMod) { 1006 //Mark this as a dependency for this plugin, so it 1007 //can be traced for cycles. 1008 this.depMaps.push(normalizedMap); 1009 1010 if (this.events.error) { 1011 normalizedMod.on(‘error‘, bind(this, function (err) { 1012 this.emit(‘error‘, err); 1013 })); 1014 } 1015 normalizedMod.enable(); 1016 } 1017 1018 return; 1019 } 1020 1021 //If a paths config, then just load that file instead to 1022 //resolve the plugin, as it is built into that paths layer. 1023 if (bundleId) { 1024 this.map.url = context.nameToUrl(bundleId); 1025 this.load(); 1026 return; 1027 } 1028 1029 load = bind(this, function (value) { 1030 this.init([], function () { return value; }, null, { 1031 enabled: true 1032 }); 1033 }); 1034 1035 load.error = bind(this, function (err) { 1036 this.inited = true; 1037 this.error = err; 1038 err.requireModules = [id]; 1039 1040 //Remove temp unnormalized modules for this module, 1041 //since they will never be resolved otherwise now. 1042 eachProp(registry, function (mod) { 1043 if (mod.map.id.indexOf(id + ‘_unnormalized‘) === 0) { 1044 cleanRegistry(mod.map.id); 1045 } 1046 }); 1047 1048 one rror(err); 1049 }); 1050 1051 //Allow plugins to load other code without having to know the 1052 //context or how to ‘complete‘ the load. 1053 load.fromText = bind(this, function (text, textAlt) { 1054 /*jslint evil: true */ 1055 var moduleName = map.name, 1056 moduleMap = makeModuleMap(moduleName), 1057 hasInteractive = useInteractive; 1058 1059 //As of 2.1.0, support just passing the text, to reinforce 1060 //fromText only being called once per resource. Still 1061 //support old style of passing moduleName but discard 1062 //that moduleName in favor of the internal ref. 1063 if (textAlt) { 1064 text = textAlt; 1065 } 1066 1067 //Turn off interactive script matching for IE for any define 1068 //calls in the text, then turn it back on at the end. 1069 if (hasInteractive) { 1070 useInteractive = false; 1071 } 1072 1073 //Prime the system by creating a module instance for 1074 //it. 1075 getModule(moduleMap); 1076 1077 //Transfer any config to this other module. 1078 if (hasProp(config.config, id)) { 1079 config.config[moduleName] = config.config[id]; 1080 } 1081 1082 try { 1083 req.exec(text); 1084 } catch (e) { 1085 return one rror(makeError(‘fromtexteval‘, 1086 ‘fromText eval for ‘ + id + 1087 ‘ failed: ‘ + e, 1088 e, 1089 [id])); 1090 } 1091 1092 if (hasInteractive) { 1093 useInteractive = true; 1094 } 1095 1096 //Mark this as a dependency for the plugin 1097 //resource 1098 this.depMaps.push(moduleMap); 1099 1100 //Support anonymous modules. 1101 context.completeLoad(moduleName); 1102 1103 //Bind the value of that module to the value for this 1104 //resource ID. 1105 localRequire([moduleName], load); 1106 }); 1107 1108 //Use parentName here since the plugin‘s name is not reliable, 1109 //could be some weird string with no path that actually wants to 1110 //reference the parentName‘s path. 1111 plugin.load(map.name, localRequire, load, config); 1112 })); 1113 1114 context.enable(pluginMap, this); 1115 this.pluginMaps[pluginMap.id] = pluginMap; 1116 }, 1117 1118 enable: function () { 1119 enabledRegistry[this.map.id] = this; 1120 this.enabled = true; 1121 1122 //Set flag mentioning that the module is enabling, 1123 //so that immediate calls to the defined callbacks 1124 //for dependencies do not trigger inadvertent load 1125 //with the depCount still being zero. 1126 this.enabling = true; 1127 1128 //Enable each dependency 1129 each(this.depMaps, bind(this, function (depMap, i) { 1130 var id, mod, handler; 1131 1132 if (typeof depMap === ‘string‘) { 1133 //Dependency needs to be converted to a depMap 1134 //and wired up to this module. 1135 depMap = makeModuleMap(depMap, 1136 (this.map.isDefine ? this.map : this.map.parentMap), 1137 false, 1138 !this.skipMap); 1139 this.depMaps[i] = depMap; 1140 1141 handler = getOwn(handlers, depMap.id); 1142 1143 if (handler) { 1144 this.depExports[i] = handler(this); 1145 return; 1146 } 1147 1148 this.depCount += 1; 1149 1150 on(depMap, ‘defined‘, bind(this, function (depExports) { 1151 if (this.undefed) { 1152 return; 1153 } 1154 this.defineDep(i, depExports); 1155 this.check(); 1156 })); 1157 1158 if (this.errback) { 1159 on(depMap, ‘error‘, bind(this, this.errback)); 1160 } else if (this.events.error) { 1161 // No direct errback on this module, but something 1162 // else is listening for errors, so be sure to 1163 // propagate the error correctly. 1164 on(depMap, ‘error‘, bind(this, function(err) { 1165 this.emit(‘error‘, err); 1166 })); 1167 } 1168 } 1169 1170 id = depMap.id; 1171 mod = registry[id]; 1172 1173 //Skip special modules like ‘require‘, ‘exports‘, ‘module‘ 1174 //Also, don‘t call enable if it is already enabled, 1175 //important in circular dependency cases. 1176 if (!hasProp(handlers, id) && mod && !mod.enabled) { 1177 context.enable(depMap, this); 1178 } 1179 })); 1180 1181 //Enable each plugin that is used in 1182 //a dependency 1183 eachProp(this.pluginMaps, bind(this, function (pluginMap) { 1184 var mod = getOwn(registry, pluginMap.id); 1185 if (mod && !mod.enabled) { 1186 context.enable(pluginMap, this); 1187 } 1188 })); 1189 1190 this.enabling = false; 1191 1192 this.check(); 1193 }, 1194 1195 on: function (name, cb) { 1196 var cbs = this.events[name]; 1197 if (!cbs) { 1198 cbs = this.events[name] = []; 1199 } 1200 cbs.push(cb); 1201 }, 1202 1203 emit: function (name, evt) { 1204 each(this.events[name], function (cb) { 1205 cb(evt); 1206 }); 1207 if (name === ‘error‘) { 1208 //Now that the error handler was triggered, remove 1209 //the listeners, since this broken Module instance 1210 //can stay around for a while in the registry. 1211 delete this.events[name]; 1212 } 1213 } 1214 }; 1215 1216 /*-----------------------------------------end--------------------------------*/ 1217 /* 1218 * 1219 * 1220 * 1221 * */ 1222 /*-----------------------------------------start--------------------------------*/ 1223 //num = 11 1224 1225 //init: function (depMaps, factory, errback, options) {} 1226 1227 this.factory = factory; 1228 this.depMaps = depMaps && depMaps.slice(0); 1229 1230 this.errback = errback; 1231 1232 //Indicate this module has be initialized 1233 this.inited = true; 1234 1235 this.ignore = options.ignore; 1236 1237 //总结一句话 就是给module.绑定数据。 1238 /*----------------------------------------end-------------------------*/ 1239 /* 1240 * 1241 * */ 1242 /*----------------------------------------start-------------------------*/ 1243 num == 12 1244 1245 1246 /*----------------------------------------end-------------------------*/ 1247 /* 1248 * 1249 * */
/*---------------------------------------start-------------------------------*/
req({}); // num == 1 跳到 num == 2
//Exports some context-sensitive methods on global require.
each([
‘toUrl‘,
‘undef‘,
‘defined‘,
‘specified‘
], function (prop) {
//Reference from contexts instead of early binding to default context,
//so that during builds, the latest instance of the default context
//with its config gets used.
req[prop] = function () {
var ctx = contexts[defContextName];
return ctx.require[prop].apply(ctx, arguments);
};
});
if (isBrowser && !cfg.skipDataMain) {} //req.deps[mainscript]
//Set up with config info.
req(cfg); //最后启动。 按照之前写的num 一步一步的去加载。
/*----------------------------------------start---------------------------------*/
//第一次 num == 2
//params
var deps = {},
callback = undefined,
errback = undefined,
optional = undefined;
//--------------声明------------------
var context = undefined,
config = undefined,
contextName = defContextName;
//-------------判断---------------
config = {};
deps = [];
//------------判断--------------
context = contexts[contextName] = req.s.newContext(contextName); //跳到num ==3
//时间上就是执行 localRequire(deps, callback, errback);
context.require(deps, callback, errback); //跳到 num ==5
/*---------------------------------------end-------------------------------*/
/*
*
*
* */
/*---------------------------------------start-------------------------------*/
//-----------------------进入核心函数--------------------------
//第一次
//function newContext(contextName) num == 3
context = {
config: config,
contextName: contextName,
registry: registry,
defined: defined,
urlFetched: urlFetched,
defQueue: defQueue,
defQueueMap: {},
Module: Module,
makeModuleMap: makeModuleMap,
nextTick: req.nextTick,
onError: one rror,
/**
* Set a configuration for the context.
* @param {Object} cfg config object to integrate.
*/
configure: function (cfg) {
//Make sure the baseUrl ends in a slash.
if (cfg.baseUrl) {
if (cfg.baseUrl.charAt(cfg.baseUrl.length - 1) !== ‘/‘) {
cfg.baseUrl += ‘/‘;
}
}
// Convert old style urlArgs string to a function.
if (typeof cfg.urlArgs === ‘string‘) {
var urlArgs = cfg.urlArgs;
cfg.urlArgs = function(id, url) {
return (url.indexOf(‘?‘) === -1 ? ‘?‘ : ‘&‘) + urlArgs;
};
}
//Save off the paths since they require special processing,
//they are additive.
var shim = config.shim,
objs = {
paths: true,
bundles: true,
config: true,
map: true
};
eachProp(cfg, function (value, prop) {
if (objs[prop]) {
if (!config[prop]) {
config[prop] = {};
}
mixin(config[prop], value, true, true);
} else {
config[prop] = value;
}
});
//Reverse map the bundles
if (cfg.bundles) {
eachProp(cfg.bundles, function (value, prop) {
each(value, function (v) {
if (v !== prop) {
bundlesMap[v] = prop;
}
});
});
}
//Merge shim
if (cfg.shim) {
eachProp(cfg.shim, function (value, id) {
//Normalize the structure
if (isArray(value)) {
value = http://www.mamicode.com/{
deps: value
};
}
if ((value.exports || value.init) && !value.exportsFn) {
value.exportsFn = context.makeShimExports(value);
}
shim[id] = value;
});
config.shim = shim;
}
//Adjust packages if necessary.
if (cfg.packages) {
each(cfg.packages, function (pkgObj) {
var location, name;
pkgObj = typeof pkgObj === ‘string‘ ? {name: pkgObj} : pkgObj;
name = pkgObj.name;
location = pkgObj.location;
if (location) {
config.paths[name] = pkgObj.location;
}
//Save pointer to main module ID for pkg name.
//Remove leading dot in main, so main paths are normalized,
//and remove any trailing .js, since different package
//envs have different conventions: some use a module name,
//some use a file name.
config.pkgs[name] = pkgObj.name + ‘/‘ + (pkgObj.main || ‘main‘)
.replace(currDirRegExp, ‘‘)
.replace(jsSuffixRegExp, ‘‘);
});
}
//If there are any "waiting to execute" modules in the registry,
//update the maps for them, since their info, like URLs to load,
//may have changed.
eachProp(registry, function (mod, id) {
//If module already has init called, since it is too
//late to modify them, and ignore unnormalized ones
//since they are transient.
if (!mod.inited && !mod.map.unnormalized) {
mod.map = makeModuleMap(id, null, true);
}
});
//If a deps array or a config callback is specified, then call
//require with those args. This is useful when require is defined as a
//config object before require.js is loaded.
if (cfg.deps || cfg.callback) {
context.require(cfg.deps || [], cfg.callback);
}
},
makeShimExports: function (value) {
function fn() {
var ret;
if (value.init) {
ret = value.init.apply(global, arguments);
}
return ret || (value.exports && getGlobal(value.exports));
}
return fn;
},
makeRequire: function (relMap, options) {
options = options || {};
function localRequire(deps, callback, errback) {
var id, map, requireMod;
if (options.enableBuildCallback && callback && isFunction(callback)) {
callback.__requireJsBuild = true;
}
if (typeof deps === ‘string‘) {
if (isFunction(callback)) {
//Invalid call
return onError(makeError(‘requireargs‘, ‘Invalid require call‘), errback);
}
//If require|exports|module are requested, get the
//value for them from the special handlers. Caveat:
//this only works while module is being defined.
if (relMap && hasProp(handlers, deps)) {
return handlers[deps](registry[relMap.id]);
}
//Synchronous access to one module. If require.get is
//available (as in the Node adapter), prefer that.
if (req.get) {
return req.get(context, deps, relMap, localRequire);
}
//Normalize module name, if it contains . or ..
map = makeModuleMap(deps, relMap, false, true);
id = map.id;
if (!hasProp(defined, id)) {
return onError(makeError(‘notloaded‘, ‘Module name "‘ +
id +
‘" has not been loaded yet for context: ‘ +
contextName +
(relMap ? ‘‘ : ‘. Use require([])‘)));
}
return defined[id];
}
//Grab defines waiting in the global queue.
intakeDefines();
//Mark all the dependencies as needing to be loaded.
context.nextTick(function () {
//Some defines could have been added since the
//require call, collect them.
intakeDefines();
requireMod = getModule(makeModuleMap(null, relMap));
//Store if map config should be applied to this require
//call for dependencies.
requireMod.skipMap = options.skipMap;
requireMod.init(deps, callback, errback, {
enabled: true
});
checkLoaded();
});
return localRequire;
}
mixin(localRequire, {
isBrowser: isBrowser,
/**
* Converts a module name + .extension into an URL path.
* *Requires* the use of a module name. It does not support using
* plain URLs like nameToUrl.
*/
toUrl: function (moduleNamePlusExt) {
var ext,
index = moduleNamePlusExt.lastIndexOf(‘.‘),
segment = moduleNamePlusExt.split(‘/‘)[0],
isRelative = segment === ‘.‘ || segment === ‘..‘;
//Have a file extension alias, and it is not the
//dots from a relative path.
if (index !== -1 && (!isRelative || index > 1)) {
ext = moduleNamePlusExt.substring(index, moduleNamePlusExt.length);
moduleNamePlusExt = moduleNamePlusExt.substring(0, index);
}
return context.nameToUrl(normalize(moduleNamePlusExt,
relMap && relMap.id, true), ext, true);
},
defined: function (id) {
return hasProp(defined, makeModuleMap(id, relMap, false, true).id);
},
specified: function (id) {
id = makeModuleMap(id, relMap, false, true).id;
return hasProp(defined, id) || hasProp(registry, id);
}
});
//Only allow undef on top level require calls
if (!relMap) {
localRequire.undef = function (id) {
//Bind any waiting define() calls to this context,
//fix for #408
takeGlobalQueue();
var map = makeModuleMap(id, relMap, true),
mod = getOwn(registry, id);
mod.undefed = true;
removeScript(id);
delete defined[id];
delete urlFetched[map.url];
delete undefEvents[id];
//Clean queued defines too. Go backwards
//in array so that the splices do not
//mess up the iteration.
eachReverse(defQueue, function(args, i) {
if (args[0] === id) {
defQueue.splice(i, 1);
}
});
delete context.defQueueMap[id];
if (mod) {
//Hold on to listeners in case the
//module will be attempted to be reloaded
//using a different config.
if (mod.events.defined) {
undefEvents[id] = mod.events;
}
cleanRegistry(id);
}
};
}
return localRequire;
},
/**
* Called to enable a module if it is still in the registry
* awaiting enablement. A second arg, parent, the parent module,
* is passed in for context, when this method is overridden by
* the optimizer. Not shown here to keep code compact.
*/
enable: function (depMap) {
var mod = getOwn(registry, depMap.id);
if (mod) {
getModule(depMap).enable();
}
},
/**
* Internal method used by environment adapters to complete a load event.
* A load event could be a script load or just a load pass from a synchronous
* load call.
* @param {String} moduleName the name of the module to potentially complete.
*/
completeLoad: function (moduleName) {
var found, args, mod,
shim = getOwn(config.shim, moduleName) || {},
shExports = shim.exports;
takeGlobalQueue();
while (defQueue.length) {
args = defQueue.shift();
if (args[0] === null) {
args[0] = moduleName;
//If already found an anonymous module and bound it
//to this name, then this is some other anon module
//waiting for its completeLoad to fire.
if (found) {
break;
}
found = true;
} else if (args[0] === moduleName) {
//Found matching define call for this script!
found = true;
}
callGetModule(args);
}
context.defQueueMap = {};
//Do this after the cycle of callGetModule in case the result
//of those calls/init calls changes the registry.
mod = getOwn(registry, moduleName);
if (!found && !hasProp(defined, moduleName) && mod && !mod.inited) {
if (config.enforceDefine && (!shExports || !getGlobal(shExports))) {
if (hasPathFallback(moduleName)) {
return;
} else {
return onError(makeError(‘nodefine‘,
‘No define call for ‘ + moduleName,
null,
[moduleName]));
}
} else {
//A script that does not call define(), so just simulate
//the call for it.
callGetModule([moduleName, (shim.deps || []), shim.exportsFn]);
}
}
checkLoaded();
},
/**
* Converts a module name to a file path. Supports cases where
* moduleName may actually be just an URL.
* Note that it **does not** call normalize on the moduleName,
* it is assumed to have already been normalized. This is an
* internal API, not a public one. Use toUrl for the public API.
*/
nameToUrl: function (moduleName, ext, skipExt) {
var paths, syms, i, parentModule, url,
parentPath, bundleId,
pkgMain = getOwn(config.pkgs, moduleName);
if (pkgMain) {
moduleName = pkgMain;
}
bundleId = getOwn(bundlesMap, moduleName);
if (bundleId) {
return context.nameToUrl(bundleId, ext, skipExt);
}
//If a colon is in the URL, it indicates a protocol is used and it is just
//an URL to a file, or if it starts with a slash, contains a query arg (i.e. ?)
//or ends with .js, then assume the user meant to use an url and not a module id.
//The slash is important for protocol-less URLs as well as full paths.
if (req.jsExtRegExp.test(moduleName)) {
//Just a plain path, not module name lookup, so just return it.
//Add extension if it is included. This is a bit wonky, only non-.js things pass
//an extension, this method probably needs to be reworked.
url = moduleName + (ext || ‘‘);
} else {
//A module that needs to be converted to a path.
paths = config.paths;
syms = moduleName.split(‘/‘);
//For each module name segment, see if there is a path
//registered for it. Start with most specific name
//and work up from it.
for (i = syms.length; i > 0; i -= 1) {
parentModule = syms.slice(0, i).join(‘/‘);
parentPath = getOwn(paths, parentModule);
if (parentPath) {
//If an array, it means there are a few choices,
//Choose the one that is desired
if (isArray(parentPath)) {
parentPath = parentPath[0];
}
syms.splice(0, i, parentPath);
break;
}
}
//Join the path parts together, then figure out if baseUrl is needed.
url = syms.join(‘/‘);
url += (ext || (/^data\:|^blob\:|\?/.test(url) || skipExt ? ‘‘ : ‘.js‘));
url = (url.charAt(0) === ‘/‘ || url.match(/^[\w\+\.\-]+:/) ? ‘‘ : config.baseUrl) + url;
}
return config.urlArgs && !/^blob\:/.test(url) ?
url + config.urlArgs(moduleName, url) : url;
},
//Delegates to req.load. Broken out as a separate function to
//allow overriding in the optimizer.
load: function (id, url) {
req.load(context, id, url);
},
/**
* Executes a module callback function. Broken out as a separate function
* solely to allow the build system to sequence the files in the built
* layer in the right sequence.
*
* @private
*/
execCb: function (name, callback, args, exports) {
return callback.apply(exports, args);
},
/**
* callback for script loads, used to check status of loading.
*
* @param {Event} evt the event from the browser for the script
* that was loaded.
*/
onScriptLoad: function (evt) {
//Using currentTarget instead of target for Firefox 2.0‘s sake. Not
//all old browsers will be supported, but this one was easy enough
//to support and still makes sense.
if (evt.type === ‘load‘ ||
(readyRegExp.test((evt.currentTarget || evt.srcElement).readyState))) {
//Reset interactive script so a script node is not held onto for
//to long.
interactiveScript = null;
//Pull out the name of the module and the context.
var data = getScriptData(evt);
context.completeLoad(data.id);
}
},
/**
* Callback for script errors.
*/
onScriptError: function (evt) {
var data = getScriptData(evt);
if (!hasPathFallback(data.id)) {
var parents = [];
eachProp(registry, function(value, key) {
if (key.indexOf(‘_@r‘) !== 0) {
each(value.depMaps, function(depMap) {
if (depMap.id === data.id) {
parents.push(key);
return true;
}
});
}
});
return onError(makeError(‘scripterror‘, ‘Script error for "‘ + data.id +
(parents.length ?
‘", needed by: ‘ + parents.join(‘, ‘) :
‘"‘), evt, [data.id]));
}
}
};
//得到一个闭包环境
context.require = context.makeRequire(); //跳到num ===4
//return context;
/*---------------------------------------end-------------------------------*/
/*
*
*
*
*
*
* */
/*---------------------------------------start-------------------------------*/
//--------------------------进入makeRequire------------------------
//第一次
//params [relMap , options] num == 4
var relMap = undefined,
options = {};
//声明localRequire函数
var localRequire= function(deps, callback, errback){};
//给localRequire加属性
var fn1={
isBrowser: isBrowser,
/**
* Converts a module name + .extension into an URL path.
* *Requires* the use of a module name. It does not support using
* plain URLs like nameToUrl.
*/
toUrl: function (moduleNamePlusExt) {
var ext,
index = moduleNamePlusExt.lastIndexOf(‘.‘),
segment = moduleNamePlusExt.split(‘/‘)[0],
isRelative = segment === ‘.‘ || segment === ‘..‘;
//Have a file extension alias, and it is not the
//dots from a relative path.
if (index !== -1 && (!isRelative || index > 1)) {
ext = moduleNamePlusExt.substring(index, moduleNamePlusExt.length);
moduleNamePlusExt = moduleNamePlusExt.substring(0, index);
}
return context.nameToUrl(normalize(moduleNamePlusExt,
relMap && relMap.id, true), ext, true);
},
defined: function (id) {
return hasProp(defined, makeModuleMap(id, relMap, false, true).id);
},
specified: function (id) {
id = makeModuleMap(id, relMap, false, true).id;
return hasProp(defined, id) || hasProp(registry, id);
}
};
//---------------------- 判断 if (!relMap)----------------------
//加属性
var fn2 = undef = function(id){};
//返回return localRequire;
//总结一下 就是返回一个函数,给他加了一些属性;
/*---------------------------------------end-------------------------------*/
/*
*
* */
/*---------------------------------------start-------------------------------*/
// num == 5
intakeDefines() // 调到num == 6
/*
* while (defQueue.length) {}遍历 defQueue;
*
*
*
* */
callGetModule(args); //args [id,deps,callb] 跳到num = 7
context.defQueueMap = {};
context.nextTick(function () {
//Some defines could have been added since the
//require call, collect them.
intakeDefines();
requireMod = getModule(makeModuleMap(null, relMap));
//Store if map config should be applied to this require
//call for dependencies.
requireMod.skipMap = options.skipMap;
requireMod.init(deps, callback, errback, {
enabled: true
});
checkLoaded();
}); //跳转到 12
/*---------------------------------------end-------------------------------*/
/*
*
*
*
*
* */
/*---------------------------------------start-------------------------------*/
/* function takeGlobalQueue() num == 6
* */
//把globalDefQueue 里面通过define(id,desp,callback) 都放到 特定context 下的 defQueue
//并且最后清空 globalDefQueue = [];
/*---------------------------------------end-------------------------------*/
/*
*
*
*
*
* */
/*---------------------------------------start-------------------------------*/
// function callGetModule(args) num == 7
//将 defined里没有的 id进行构建模块
if (!hasProp(defined, args[0])) {
getModule(makeModuleMap(args[0], null, true)).init(args[1], args[2]);
}
makeModuleMap(args[0], null, true) //跳转到 num== 8
getModule(makeModuleMap(args[0], null, true)) //跳转到 num == 9
getModule(makeModuleMap(args[0], null, true)).init(args[1], args[2]);//跳转到 num == 11
//生成的Module 里面的map属性 就是 makeModuleMap返回的对象。
/*---------------------------------------end-------------------------------*/
/*
*
*
*
*
* */
/*---------------------------------------start-------------------------------*/
//function makeModuleMap(name, parentModuleMap, isNormalized, applyMap) //num == 8
//返回obj
var obj = {
prefix: prefix,
name: normalizedName,
parentMap: parentModuleMap,
unnormalized: !!suffix,
url: url,
originalName: originalName,
isDefine: isDefine,
id: (prefix ?
prefix + ‘!‘ + normalizedName :
normalizedName) + suffix
};
/*---------------------------------------end-------------------------------*/
/*
*
*
*
*
* */
/*-----------------------------------------start--------------------------------*/
//function getModule(depMap) num == 9
var id = depMap.id,
mod = getOwn(registry, id);
if (!mod) {
mod = registry[id] = new context.Module(depMap);
}
new context.Module(depMap); //跳转到10
//return mod;
/*----------------------------------------end-------------------------*/
/*
*
*
*
*
* */
/*-----------------------------------------start--------------------------------*/
//num ===10
Module = function (map) {
this.events = getOwn(undefEvents, map.id) || {};
this.map = map;
this.shim = getOwn(config.shim, map.id);
this.depExports = [];
this.depMaps = [];
this.depMatched = [];
this.pluginMaps = {};
this.depCount = 0;
/* this.exports this.factory
this.depMaps = [],
this.enabled, this.fetched
*/
};
Module.prototype = {
init: function (depMaps, factory, errback, options) {
options = options || {};
//Do not do more inits if already done. Can happen if there
//are multiple define calls for the same module. That is not
//a normal, common case, but it is also not unexpected.
if (this.inited) {
return;
}
this.factory = factory;
if (errback) {
//Register for errors on this module.
this.on(‘error‘, errback);
} else if (this.events.error) {
//If no errback already, but there are error listeners
//on this module, set up an errback to pass to the deps.
errback = bind(this, function (err) {
this.emit(‘error‘, err);
});
}
//Do a copy of the dependency array, so that
//source inputs are not modified. For example
//"shim" deps are passed in here directly, and
//doing a direct modification of the depMaps array
//would affect that config.
this.depMaps = depMaps && depMaps.slice(0);
this.errback = errback;
//Indicate this module has be initialized
this.inited = true;
this.ignore = options.ignore;
//Could have option to init this module in enabled mode,
//or could have been previously marked as enabled. However,
//the dependencies are not known until init is called. So
//if enabled previously, now trigger dependencies as enabled.
if (options.enabled || this.enabled) {
//Enable this module and dependencies.
//Will call this.check()
this.enable();
} else {
this.check();
}
},
defineDep: function (i, depExports) {
//Because of cycles, defined callback for a given
//export can be called more than once.
if (!this.depMatched[i]) {
this.depMatched[i] = true;
this.depCount -= 1;
this.depExports[i] = depExports;
}
},
fetch: function () {
if (this.fetched) {
return;
}
this.fetched = true;
context.startTime = (new Date()).getTime();
var map = this.map;
//If the manager is for a plugin managed resource,
//ask the plugin to load it now.
if (this.shim) {
context.makeRequire(this.map, {
enableBuildCallback: true
})(this.shim.deps || [], bind(this, function () {
return map.prefix ? this.callPlugin() : this.load();
}));
} else {
//Regular dependency.
return map.prefix ? this.callPlugin() : this.load();
}
},
load: function () {
var url = this.map.url;
//Regular dependency.
if (!urlFetched[url]) {
urlFetched[url] = true;
context.load(this.map.id, url);
}
},
/**
* Checks if the module is ready to define itself, and if so,
* define it.
*/
check: function () {
if (!this.enabled || this.enabling) {
return;
}
var err, cjsModule,
id = this.map.id,
depExports = this.depExports,
exports = this.exports,
factory = this.factory;
if (!this.inited) {
// Only fetch if not already in the defQueue.
if (!hasProp(context.defQueueMap, id)) {
this.fetch();
}
} else if (this.error) {
this.emit(‘error‘, this.error);
} else if (!this.defining) {
//The factory could trigger another require call
//that would result in checking this module to
//define itself again. If already in the process
//of doing that, skip this work.
this.defining = true;
if (this.depCount < 1 && !this.defined) {
if (isFunction(factory)) {
//If there is an error listener, favor passing
//to that instead of throwing an error. However,
//only do it for define()‘d modules. require
//errbacks should not be called for failures in
//their callbacks (#699). However if a global
//onError is set, use that.
if ((this.events.error && this.map.isDefine) ||
req.onError !== defaultOnError) {
try {
exports = context.execCb(id, factory, depExports, exports);
} catch (e) {
err = e;
}
} else {
exports = context.execCb(id, factory, depExports, exports);
}
// Favor return value over exports. If node/cjs in play,
// then will not have a return value anyway. Favor
// module.exports assignment over exports object.
if (this.map.isDefine && exports === undefined) {
cjsModule = this.module;
if (cjsModule) {
exports = cjsModule.exports;
} else if (this.usingExports) {
//exports already set the defined value.
exports = this.exports;
}
}
if (err) {
err.requireMap = this.map;
err.requireModules = this.map.isDefine ? [this.map.id] : null;
err.requireType = this.map.isDefine ? ‘define‘ : ‘require‘;
return onError((this.error = err));
}
} else {
//Just a literal value
exports = factory;
}
this.exports = exports;
if (this.map.isDefine && !this.ignore) {
defined[id] = exports;
if (req.onResourceLoad) {
var resLoadMaps = [];
each(this.depMaps, function (depMap) {
resLoadMaps.push(depMap.normalizedMap || depMap);
});
req.onResourceLoad(context, this.map, resLoadMaps);
}
}
//Clean up
cleanRegistry(id);
this.defined = true;
}
//Finished the define stage. Allow calling check again
//to allow define notifications below in the case of a
//cycle.
this.defining = false;
if (this.defined && !this.defineEmitted) {
this.defineEmitted = true;
this.emit(‘defined‘, this.exports);
this.defineEmitComplete = true;
}
}
},
callPlugin: function () {
var map = this.map,
id = map.id,
//Map already normalized the prefix.
pluginMap = makeModuleMap(map.prefix);
//Mark this as a dependency for this plugin, so it
//can be traced for cycles.
this.depMaps.push(pluginMap);
on(pluginMap, ‘defined‘, bind(this, function (plugin) {
var load, normalizedMap, normalizedMod,
bundleId = getOwn(bundlesMap, this.map.id),
name = this.map.name,
parentName = this.map.parentMap ? this.map.parentMap.name : null,
localRequire = context.makeRequire(map.parentMap, {
enableBuildCallback: true
});
//If current map is not normalized, wait for that
//normalized name to load instead of continuing.
if (this.map.unnormalized) {
//Normalize the ID if the plugin allows it.
if (plugin.normalize) {
name = plugin.normalize(name, function (name) {
return normalize(name, parentName, true);
}) || ‘‘;
}
//prefix and name should already be normalized, no need
//for applying map config again either.
normalizedMap = makeModuleMap(map.prefix + ‘!‘ + name,
this.map.parentMap);
on(normalizedMap,
‘defined‘, bind(this, function (value) {
this.map.normalizedMap = normalizedMap;
this.init([], function () { return value; }, null, {
enabled: true,
ignore: true
});
}));
normalizedMod = getOwn(registry, normalizedMap.id);
if (normalizedMod) {
//Mark this as a dependency for this plugin, so it
//can be traced for cycles.
this.depMaps.push(normalizedMap);
if (this.events.error) {
normalizedMod.on(‘error‘, bind(this, function (err) {
this.emit(‘error‘, err);
}));
}
normalizedMod.enable();
}
return;
}
//If a paths config, then just load that file instead to
//resolve the plugin, as it is built into that paths layer.
if (bundleId) {
this.map.url = context.nameToUrl(bundleId);
this.load();
return;
}
load = bind(this, function (value) {
this.init([], function () { return value; }, null, {
enabled: true
});
});
load.error = bind(this, function (err) {
this.inited = true;
this.error = err;
err.requireModules = [id];
//Remove temp unnormalized modules for this module,
//since they will never be resolved otherwise now.
eachProp(registry, function (mod) {
if (mod.map.id.indexOf(id + ‘_unnormalized‘) === 0) {
cleanRegistry(mod.map.id);
}
});
one rror(err);
});
//Allow plugins to load other code without having to know the
//context or how to ‘complete‘ the load.
load.fromText = bind(this, function (text, textAlt) {
/*jslint evil: true */
var moduleName = map.name,
moduleMap = makeModuleMap(moduleName),
hasInteractive = useInteractive;
//As of 2.1.0, support just passing the text, to reinforce
//fromText only being called once per resource. Still
//support old style of passing moduleName but discard
//that moduleName in favor of the internal ref.
if (textAlt) {
text = textAlt;
}
//Turn off interactive script matching for IE for any define
//calls in the text, then turn it back on at the end.
if (hasInteractive) {
useInteractive = false;
}
//Prime the system by creating a module instance for
//it.
getModule(moduleMap);
//Transfer any config to this other module.
if (hasProp(config.config, id)) {
config.config[moduleName] = config.config[id];
}
try {
req.exec(text);
} catch (e) {
return onError(makeError(‘fromtexteval‘,
‘fromText eval for ‘ + id +
‘ failed: ‘ + e,
e,
[id]));
}
if (hasInteractive) {
useInteractive = true;
}
//Mark this as a dependency for the plugin
//resource
this.depMaps.push(moduleMap);
//Support anonymous modules.
context.completeLoad(moduleName);
//Bind the value of that module to the value for this
//resource ID.
localRequire([moduleName], load);
});
//Use parentName here since the plugin‘s name is not reliable,
//could be some weird string with no path that actually wants to
//reference the parentName‘s path.
plugin.load(map.name, localRequire, load, config);
}));
context.enable(pluginMap, this);
this.pluginMaps[pluginMap.id] = pluginMap;
},
enable: function () {
enabledRegistry[this.map.id] = this;
this.enabled = true;
//Set flag mentioning that the module is enabling,
//so that immediate calls to the defined callbacks
//for dependencies do not trigger inadvertent load
//with the depCount still being zero.
this.enabling = true;
//Enable each dependency
each(this.depMaps, bind(this, function (depMap, i) {
var id, mod, handler;
if (typeof depMap === ‘string‘) {
//Dependency needs to be converted to a depMap
//and wired up to this module.
depMap = makeModuleMap(depMap,
(this.map.isDefine ? this.map : this.map.parentMap),
false,
!this.skipMap);
this.depMaps[i] = depMap;
handler = getOwn(handlers, depMap.id);
if (handler) {
this.depExports[i] = handler(this);
return;
}
this.depCount += 1;
on(depMap, ‘defined‘, bind(this, function (depExports) {
if (this.undefed) {
return;
}
this.defineDep(i, depExports);
this.check();
}));
if (this.errback) {
on(depMap, ‘error‘, bind(this, this.errback));
} else if (this.events.error) {
// No direct errback on this module, but something
// else is listening for errors, so be sure to
// propagate the error correctly.
on(depMap, ‘error‘, bind(this, function(err) {
this.emit(‘error‘, err);
}));
}
}
id = depMap.id;
mod = registry[id];
//Skip special modules like ‘require‘, ‘exports‘, ‘module‘
//Also, don‘t call enable if it is already enabled,
//important in circular dependency cases.
if (!hasProp(handlers, id) && mod && !mod.enabled) {
context.enable(depMap, this);
}
}));
//Enable each plugin that is used in
//a dependency
eachProp(this.pluginMaps, bind(this, function (pluginMap) {
var mod = getOwn(registry, pluginMap.id);
if (mod && !mod.enabled) {
context.enable(pluginMap, this);
}
}));
this.enabling = false;
this.check();
},
on: function (name, cb) {
var cbs = this.events[name];
if (!cbs) {
cbs = this.events[name] = [];
}
cbs.push(cb);
},
emit: function (name, evt) {
each(this.events[name], function (cb) {
cb(evt);
});
if (name === ‘error‘) {
//Now that the error handler was triggered, remove
//the listeners, since this broken Module instance
//can stay around for a while in the registry.
delete this.events[name];
}
}
};
/*-----------------------------------------end--------------------------------*/
/*
*
*
*
* */
/*-----------------------------------------start--------------------------------*/
//num = 11
//init: function (depMaps, factory, errback, options) {}
this.factory = factory;
this.depMaps = depMaps && depMaps.slice(0);
this.errback = errback;
//Indicate this module has be initialized
this.inited = true;
this.ignore = options.ignore;
//总结一句话 就是给module.绑定数据。
/*----------------------------------------end-------------------------*/
/*
*
* */
/*----------------------------------------start-------------------------*/
num == 12
/*----------------------------------------end-------------------------*/
/*
*
* */
requirejs--源码分析
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