Эта проблема

В настоящее время я работаю над библиотекой JavaScript, и чтобы уменьшить количество ошибок, я подумал, что моя библиотека может выиграть от использования механизма статической типизации Dart. Во-первых, потому что моя библиотека не взаимодействовала ни с HTML, ни с другими библиотеками JavaScript, а только с чисто манипуляционными объектами javascript. Однако я не нашел никакой информации в сети, показывающей, как можно построить библиотеку JS, используя dart. Поэтому я попытался сделать это сам, создал исходный файл дартс:

library Repo;

class Type {
  final String name;
  final TypeCategory category;

  Type(String name, TypeCategory category) : name = name, category = category {
    category.types[name] = this;
  }
}

class TypeCategory {
  final String name;
  final Map<String, Type> types = new Map();

  TypeCategory(this.name);
}

class Branch {

}

class Descriptor {

}

class TableDescriptor extends Descriptor {
  TableDescriptor.ctor() {

  }
}

class Repo {
  Descriptor descriptor(String name) {

  }

  Branch branch(String name) {

  }

  void Merge() {

  }
}


main() {
  return Repo;
}

Скомпилировал его в JavaScript, используя dart2js, чтобы посмотреть, как я это делаю:

// Generated by dart2js, the Dart to JavaScript compiler version: 1.3.6.
// The code supports the following hooks:
// dartPrint(message):
//    if this function is defined it is called instead of the Dart [print]
//    method.
//
// dartMainRunner(main, args):
//    if this function is defined, the Dart [main] method will not be invoked
//    directly. Instead, a closure that will invoke [main], and its arguments
//    [args] is passed to [dartMainRunner].
(function($) {
function dart(){ this.x = 0 }var A = new dart;
delete A.x;
var B = new dart;
delete B.x;
var C = new dart;
delete C.x;
var D = new dart;
delete D.x;
var E = new dart;
delete E.x;
var F = new dart;
delete F.x;
var G = new dart;
delete G.x;
var H = new dart;
delete H.x;
var J = new dart;
delete J.x;
var K = new dart;
delete K.x;
var L = new dart;
delete L.x;
var M = new dart;
delete M.x;
var N = new dart;
delete N.x;
var O = new dart;
delete O.x;
var P = new dart;
delete P.x;
var Q = new dart;
delete Q.x;
var R = new dart;
delete R.x;
var S = new dart;
delete S.x;
var T = new dart;
delete T.x;
var U = new dart;
delete U.x;
var V = new dart;
delete V.x;
var W = new dart;
delete W.x;
var X = new dart;
delete X.x;
var Y = new dart;
delete Y.x;
var Z = new dart;
delete Z.x;
function Isolate() {}
init();

$ = Isolate.$isolateProperties;
var $$ = {};

(function (reflectionData) {
  "use strict";
  function map(x){x={x:x};delete x.x;return x}
    function processStatics(descriptor) {
      for (var property in descriptor) {
        if (!hasOwnProperty.call(descriptor, property)) continue;
        if (property === "^") continue;
        var element = descriptor[property];
        var firstChar = property.substring(0, 1);
        var previousProperty;
        if (firstChar === "+") {
          mangledGlobalNames[previousProperty] = property.substring(1);
          var flag = descriptor[property];
          if (flag > 0) descriptor[previousProperty].$reflectable = flag;
          if (element && element.length) init.typeInformation[previousProperty] = element;
        } else if (firstChar === "@") {
          property = property.substring(1);
          $[property]["@"] = element;
        } else if (firstChar === "*") {
          globalObject[previousProperty].$defaultValues = element;
          var optionalMethods = descriptor.$methodsWithOptionalArguments;
          if (!optionalMethods) {
            descriptor.$methodsWithOptionalArguments = optionalMethods = {}
          }
          optionalMethods[property] = previousProperty;
        } else if (typeof element === "function") {
          globalObject[previousProperty = property] = element;
          functions.push(property);
          init.globalFunctions[property] = element;
        } else if (element.constructor === Array) {
          addStubs(globalObject, element, property, true, descriptor, functions);
        } else {
          previousProperty = property;
          var newDesc = {};
          var previousProp;
          for (var prop in element) {
            if (!hasOwnProperty.call(element, prop)) continue;
            firstChar = prop.substring(0, 1);
            if (prop === "static") {
              processStatics(init.statics[property] = element[prop]);
            } else if (firstChar === "+") {
              mangledNames[previousProp] = prop.substring(1);
              var flag = element[prop];
              if (flag > 0) element[previousProp].$reflectable = flag;
            } else if (firstChar === "@" && prop !== "@") {
              newDesc[prop.substring(1)]["@"] = element[prop];
            } else if (firstChar === "*") {
              newDesc[previousProp].$defaultValues = element[prop];
              var optionalMethods = newDesc.$methodsWithOptionalArguments;
              if (!optionalMethods) {
                newDesc.$methodsWithOptionalArguments = optionalMethods={}
              }
              optionalMethods[prop] = previousProp;
            } else {
              var elem = element[prop];
              if (prop !== "^" && elem != null && elem.constructor === Array && prop !== "<>") {
                addStubs(newDesc, elem, prop, false, element, []);
              } else {
                newDesc[previousProp = prop] = elem;
              }
            }
          }
          $$[property] = [globalObject, newDesc];
          classes.push(property);
        }
      }
    }
  function addStubs(descriptor, array, name, isStatic, originalDescriptor, functions) {
    var f, funcs = [originalDescriptor[name] = descriptor[name] = f = array[0]];
    f.$stubName = name;
    functions.push(name);
    for (var index = 0; index < array.length; index += 2) {
      f = array[index + 1];
      if (typeof f != "function") break;
      f.$stubName = array[index + 2];
      funcs.push(f);
      if (f.$stubName) {
        originalDescriptor[f.$stubName] = descriptor[f.$stubName] = f;
        functions.push(f.$stubName);
      }
    }
    for (var i = 0; i < funcs.length; index++, i++) {
      funcs[i].$callName = array[index + 1];
    }
    var getterStubName = array[++index];
    array = array.slice(++index);
    var requiredParameterInfo = array[0];
    var requiredParameterCount = requiredParameterInfo >> 1;
    var isAccessor = (requiredParameterInfo & 1) === 1;
    var isSetter = requiredParameterInfo === 3;
    var isGetter = requiredParameterInfo === 1;
    var optionalParameterInfo = array[1];
    var optionalParameterCount = optionalParameterInfo >> 1;
    var optionalParametersAreNamed = (optionalParameterInfo & 1) === 1;
    var isIntercepted = requiredParameterCount + optionalParameterCount != funcs[0].length;
    var functionTypeIndex = array[2];
    var unmangledNameIndex =  2 * optionalParameterCount + requiredParameterCount + 3;
    var isReflectable = array.length > unmangledNameIndex;

    if (getterStubName) {
      f = tearOff(funcs, array, isStatic, name, isIntercepted);
      f.getterStub = true;
      if (isStatic) init.globalFunctions[name] = f;
      originalDescriptor[getterStubName] = descriptor[getterStubName] = f;
      funcs.push(f);
      if (getterStubName) functions.push(getterStubName);
      f.$stubName = getterStubName;
      f.$callName = null;
      if (isIntercepted) init.interceptedNames[getterStubName] = true;
    }
    if (isReflectable) {
      for (var i = 0; i < funcs.length; i++) {
        funcs[i].$reflectable = 1;
        funcs[i].$reflectionInfo = array;
      }
      var mangledNames = isStatic ? init.mangledGlobalNames : init.mangledNames;
      var unmangledName = array[unmangledNameIndex];
      var reflectionName = unmangledName;
      if (getterStubName) mangledNames[getterStubName] = reflectionName;
      if (isSetter) {
        reflectionName += "=";
      } else if (!isGetter) {
        reflectionName += ":" + requiredParameterCount + ":" + optionalParameterCount;
      }
      mangledNames[name] = reflectionName;
      funcs[0].$reflectionName = reflectionName;
      funcs[0].$metadataIndex = unmangledNameIndex + 1;
      if (optionalParameterCount) descriptor[unmangledName + "*"] = funcs[0];
    }
  }
  function tearOffGetterNoCsp(funcs, reflectionInfo, name, isIntercepted) {
    return isIntercepted
        ? new Function("funcs", "reflectionInfo", "name", "H", "c",
            "return function tearOff_" + name + (functionCounter++)+ "(x) {" +
              "if (c === null) c = H.closureFromTearOff(" +
                  "this, funcs, reflectionInfo, false, [x], name);" +
              "return new c(this, funcs[0], x, name);" +
            "}")(funcs, reflectionInfo, name, H, null)
        : new Function("funcs", "reflectionInfo", "name", "H", "c",
            "return function tearOff_" + name + (functionCounter++)+ "() {" +
              "if (c === null) c = H.closureFromTearOff(" +
                  "this, funcs, reflectionInfo, false, [], name);" +
              "return new c(this, funcs[0], null, name);" +
            "}")(funcs, reflectionInfo, name, H, null)
  }
  function tearOffGetterCsp(funcs, reflectionInfo, name, isIntercepted) {
    var cache = null;
    return isIntercepted
        ? function(x) {
            if (cache === null) cache = H.closureFromTearOff(this, funcs, reflectionInfo, false, [x], name);
            return new cache(this, funcs[0], x, name)
          }
        : function() {
            if (cache === null) cache = H.closureFromTearOff(this, funcs, reflectionInfo, false, [], name);
            return new cache(this, funcs[0], null, name)
          }
  }
  function tearOff(funcs, reflectionInfo, isStatic, name, isIntercepted) {
    var cache;
    return isStatic
        ? function() {
            if (cache === void 0) cache = H.closureFromTearOff(this, funcs, reflectionInfo, true, [], name).prototype;
            return cache;
          }
        : tearOffGetter(funcs, reflectionInfo, name, isIntercepted);
  }
  var functionCounter = 0;
  var tearOffGetter = (typeof dart_precompiled == "function")
      ? tearOffGetterCsp : tearOffGetterNoCsp;
  if (!init.libraries) init.libraries = [];
  if (!init.mangledNames) init.mangledNames = map();
  if (!init.mangledGlobalNames) init.mangledGlobalNames = map();
  if (!init.statics) init.statics = map();
  if (!init.typeInformation) init.typeInformation = map();
  if (!init.globalFunctions) init.globalFunctions = map();
  if (!init.interceptedNames) init.interceptedNames = map();
  var libraries = init.libraries;
  var mangledNames = init.mangledNames;
  var mangledGlobalNames = init.mangledGlobalNames;
  var hasOwnProperty = Object.prototype.hasOwnProperty;
  var length = reflectionData.length;
  for (var i = 0; i < length; i++) {
    var data = reflectionData[i];
    var name = data[0];
    var uri = data[1];
    var metadata = data[2];
    var globalObject = data[3];
    var descriptor = data[4];
    var isRoot = !!data[5];
    var fields = descriptor && descriptor["^"];
    var classes = [];
    var functions = [];
    processStatics(descriptor);
    libraries.push([name, uri, classes, functions, metadata, fields, isRoot,
                    globalObject]);
  }
})
([
["Repo", "repo.dart", , F, {
  "^": "",
  main: function() {
    return C.Type_Jeh;
  }
},
1],
["_js_helper", "dart:_js_helper", , H, {
  "^": "",
  createRuntimeType: function($name) {
    return new H.TypeImpl($name, null);
  },
  TypeImpl: {
    "^": "Object;_typeName,_unmangledName"
  }
}],
["dart.core", "dart:core", , P, {
  "^": "",
  Null: {
    "^": "Object;"
  },
  Object: {
    "^": ";"
  }
}],
]);
Isolate.$finishClasses($$, $, null);
$$ = null;

// Runtime type support
// getInterceptor methods
C.Type_Jeh = H.createRuntimeType('Repo');
$.libraries_to_load = {};
$.Closure_functionCounter = 0;
$.BoundClosure_selfFieldNameCache = null;
$.BoundClosure_receiverFieldNameCache = null;

init.functionAliases = {};
;
init.metadata = [];
$ = null;
Isolate = Isolate.$finishIsolateConstructor(Isolate);
$ = new Isolate();
function convertToFastObject(properties) {
  function MyClass() {};
  MyClass.prototype = properties;
  new MyClass();
  return properties;
}
A = convertToFastObject(A);
B = convertToFastObject(B);
C = convertToFastObject(C);
D = convertToFastObject(D);
E = convertToFastObject(E);
F = convertToFastObject(F);
G = convertToFastObject(G);
H = convertToFastObject(H);
J = convertToFastObject(J);
K = convertToFastObject(K);
L = convertToFastObject(L);
M = convertToFastObject(M);
N = convertToFastObject(N);
O = convertToFastObject(O);
P = convertToFastObject(P);
Q = convertToFastObject(Q);
R = convertToFastObject(R);
S = convertToFastObject(S);
T = convertToFastObject(T);
U = convertToFastObject(U);
V = convertToFastObject(V);
W = convertToFastObject(W);
X = convertToFastObject(X);
Y = convertToFastObject(Y);
Z = convertToFastObject(Z);
// BEGIN invoke [main].
;(function (callback) {
  if (typeof document === "undefined") {
    callback(null);
    return;
  }
  if (document.currentScript) {
    callback(document.currentScript);
    return;
  }

  var scripts = document.scripts;
  function onLoad(event) {
    for (var i = 0; i < scripts.length; ++i) {
      scripts[i].removeEventListener("load", onLoad, false);
    }
    callback(event.target);
  }
  for (var i = 0; i < scripts.length; ++i) {
    scripts[i].addEventListener("load", onLoad, false);
  }
})(function(currentScript) {
  init.currentScript = currentScript;

  if (typeof dartMainRunner === "function") {
    dartMainRunner(F.main, []);
  } else {
    F.main([]);
  }
});
// END invoke [main].
function init() {
  Isolate.$isolateProperties = {};
  function generateAccessor(fieldDescriptor, accessors, cls) {
    var fieldInformation = fieldDescriptor.split("-");
    var field = fieldInformation[0];
    var len = field.length;
    var code = field.charCodeAt(len - 1);
    var reflectable;
    if (fieldInformation.length > 1)
      reflectable = true;
    else
      reflectable = false;
    code = code >= 60 && code <= 64 ? code - 59 : code >= 123 && code <= 126 ? code - 117 : code >= 37 && code <= 43 ? code - 27 : 0;
    if (code) {
      var getterCode = code & 3;
      var setterCode = code >> 2;
      var accessorName = field = field.substring(0, len - 1);
      var divider = field.indexOf(":");
      if (divider > 0) {
        accessorName = field.substring(0, divider);
        field = field.substring(divider + 1);
      }
      if (getterCode) {
        var args = getterCode & 2 ? "receiver" : "";
        var receiver = getterCode & 1 ? "this" : "receiver";
        var body = "return " + receiver + "." + field;
        var property = cls + ".prototype.get$" + accessorName + "=";
        var fn = "function(" + args + "){" + body + "}";
        if (reflectable)
          accessors.push(property + "$reflectable(" + fn + ");\n");
        else
          accessors.push(property + fn + ";\n");
      }
      if (setterCode) {
        var args = setterCode & 2 ? "receiver, value" : "value";
        var receiver = setterCode & 1 ? "this" : "receiver";
        var body = receiver + "." + field + " = value";
        var property = cls + ".prototype.set$" + accessorName + "=";
        var fn = "function(" + args + "){" + body + "}";
        if (reflectable)
          accessors.push(property + "$reflectable(" + fn + ");\n");
        else
          accessors.push(property + fn + ";\n");
      }
    }
    return field;
  }
  Isolate.$isolateProperties.$generateAccessor = generateAccessor;
  function defineClass(name, cls, fields) {
    var accessors = [];
    var str = "function " + cls + "(";
    var body = "";
    for (var i = 0; i < fields.length; i++) {
      if (i != 0)
        str += ", ";
      var field = generateAccessor(fields[i], accessors, cls);
      var parameter = "parameter_" + field;
      str += parameter;
      body += "this." + field + " = " + parameter + ";\n";
    }
    str += ") {\n" + body + "}\n";
    str += cls + ".builtin$cls=\"" + name + "\";\n";
    str += "$desc=$collectedClasses." + cls + ";\n";
    str += "if($desc instanceof Array) $desc = $desc[1];\n";
    str += cls + ".prototype = $desc;\n";
    if (typeof defineClass.name != "string") {
      str += cls + ".name=\"" + cls + "\";\n";
    }
    str += accessors.join("");
    return str;
  }
  var inheritFrom = function() {
    function tmp() {
    }
    var hasOwnProperty = Object.prototype.hasOwnProperty;
    return function(constructor, superConstructor) {
      tmp.prototype = superConstructor.prototype;
      var object = new tmp();
      var properties = constructor.prototype;
      for (var member in properties)
        if (hasOwnProperty.call(properties, member))
          object[member] = properties[member];
      object.constructor = constructor;
      constructor.prototype = object;
      return object;
    };
  }();
  Isolate.$finishClasses = function(collectedClasses, isolateProperties, existingIsolateProperties) {
    var pendingClasses = {};
    if (!init.allClasses)
      init.allClasses = {};
    var allClasses = init.allClasses;
    var hasOwnProperty = Object.prototype.hasOwnProperty;
    if (typeof dart_precompiled == "function") {
      var constructors = dart_precompiled(collectedClasses);
    } else {
      var combinedConstructorFunction = "function $reflectable(fn){fn.$reflectable=1;return fn};\n" + "var $desc;\n";
      var constructorsList = [];
    }
    for (var cls in collectedClasses) {
      if (hasOwnProperty.call(collectedClasses, cls)) {
        var desc = collectedClasses[cls];
        if (desc instanceof Array)
          desc = desc[1];
        var classData = desc["^"], supr, name = cls, fields = classData;
        if (typeof classData == "string") {
          var split = classData.split("/");
          if (split.length == 2) {
            name = split[0];
            fields = split[1];
          }
        }
        var s = fields.split(";");
        fields = s[1] == "" ? [] : s[1].split(",");
        supr = s[0];
        split = supr.split(":");
        if (split.length == 2) {
          supr = split[0];
          var functionSignature = split[1];
          if (functionSignature)
            desc.$signature = function(s) {
              return function() {
                return init.metadata[s];
              };
            }(functionSignature);
        }
        if (typeof dart_precompiled != "function") {
          combinedConstructorFunction += defineClass(name, cls, fields);
          constructorsList.push(cls);
        }
        if (supr)
          pendingClasses[cls] = supr;
      }
    }
    if (typeof dart_precompiled != "function") {
      combinedConstructorFunction += "return [\n  " + constructorsList.join(",\n  ") + "\n]";
      var constructors = new Function("$collectedClasses", combinedConstructorFunction)(collectedClasses);
      combinedConstructorFunction = null;
    }
    for (var i = 0; i < constructors.length; i++) {
      var constructor = constructors[i];
      var cls = constructor.name;
      var desc = collectedClasses[cls];
      var globalObject = isolateProperties;
      if (desc instanceof Array) {
        globalObject = desc[0] || isolateProperties;
        desc = desc[1];
      }
      allClasses[cls] = constructor;
      globalObject[cls] = constructor;
    }
    constructors = null;
    var finishedClasses = {};
    init.interceptorsByTag = Object.create(null);
    init.leafTags = {};
    function finishClass(cls) {
      var hasOwnProperty = Object.prototype.hasOwnProperty;
      if (hasOwnProperty.call(finishedClasses, cls))
        return;
      finishedClasses[cls] = true;
      var superclass = pendingClasses[cls];
      if (!superclass || typeof superclass != "string")
        return;
      finishClass(superclass);
      var constructor = allClasses[cls];
      var superConstructor = allClasses[superclass];
      if (!superConstructor)
        superConstructor = existingIsolateProperties[superclass];
      var prototype = inheritFrom(constructor, superConstructor);
    }
    for (var cls in pendingClasses)
      finishClass(cls);
  };
  Isolate.$lazy = function(prototype, staticName, fieldName, getterName, lazyValue) {
    var sentinelUndefined = {};
    var sentinelInProgress = {};
    prototype[fieldName] = sentinelUndefined;
    prototype[getterName] = function() {
      var result = $[fieldName];
      try {
        if (result === sentinelUndefined) {
          $[fieldName] = sentinelInProgress;
          try {
            result = $[fieldName] = lazyValue();
          } finally {
            if (result === sentinelUndefined) {
              if ($[fieldName] === sentinelInProgress) {
                $[fieldName] = null;
              }
            }
          }
        } else {
          if (result === sentinelInProgress)
            H.throwCyclicInit(staticName);
        }
        return result;
      } finally {
        $[getterName] = function() {
          return this[fieldName];
        };
      }
    };
  };
  Isolate.$finishIsolateConstructor = function(oldIsolate) {
    var isolateProperties = oldIsolate.$isolateProperties;
    function Isolate() {
      var hasOwnProperty = Object.prototype.hasOwnProperty;
      for (var staticName in isolateProperties)
        if (hasOwnProperty.call(isolateProperties, staticName))
          this[staticName] = isolateProperties[staticName];
      function ForceEfficientMap() {
      }
      ForceEfficientMap.prototype = this;
      new ForceEfficientMap();
    }
    Isolate.prototype = oldIsolate.prototype;
    Isolate.prototype.constructor = Isolate;
    Isolate.$isolateProperties = isolateProperties;
    Isolate.$finishClasses = oldIsolate.$finishClasses;
    return Isolate;
  };
}
})()

//# sourceMappingURL=out.js.map
//@ sourceMappingURL=out.js.map

И все, я выбросил Дарт, потому что я не знал, что делать с сгенерированным файлом JS, а также я боялся потенциально большого количества времени, необходимого для поддержания чистоты получаемого интерфейса библиотеки и аналогичного тому, который я использую с JavaScript.

Вопросы)Как открыть определения классов, созданные в Dart, а затем использовать их в JavaScript?Как вы думаете, стоит ли идти в Дарт, когда почти все потенциальные пользователи библиотеки будут использовать вместо этого версию JS? (Использование дротика уже не очень хорошо для меня из-за различий в размерах сообщества, это означает, что меньше людей с легкостью смогут внести свой вклад в мою библиотеку)По вашему мнению, что мне делать?