我有以下飞镖代码：
$ cat helloworld.dart
main() => print('Hello world!');
$
dart编译器针对上述代码生成的javascript代码如下：
$ cat helloworld.dart.app.js
function native_ListFactory__new(typeToken, length) {
return RTT.setTypeInfo(
new Array(length),
Array.$lookupRTT(RTT.getTypeInfo(typeToken).typeArgs));
}
function native_ListImplementation__indexOperator(index) {
return this[index];
}
function native_ListImplementation__indexAssignOperator(index, value) {
this[index] = value;
}
function native_ListImplementation_get$length() {
return this.length;
}
function native_ListImplementation__setLength(length) {
this.length = length;
}
function native_ListImplementation__add(element) {
this.push(element);
}
function native_BoolImplementation_EQ(other) {
return typeof other == 'boolean' && this == other;
}
function native_BoolImplementation_toString() {
return this.toString();
}
<snapped>
var static$uninitialized = {};
var static$initializing = {};
function $inherits(child, parent) {
if (child.prototype.__proto__) {
child.prototype.__proto__ = parent.prototype;
} else {
function tmp() {};
tmp.prototype = parent.prototype;
child.prototype = new tmp();
child.prototype.constructor = child;
}
}
isolate$inits.push(function(){
isolate$current.Duration$DartMILLISECONDS_PER_MINUTE$field = static$uninitialized;
isolate$current.Duration$DartMILLISECONDS_PER_HOUR$field = static$uninitialized;
isolate$current.Duration$DartMILLISECONDS_PER_DAY$field = static$uninitialized;
isolate$current.Duration$DartSECONDS_PER_HOUR$field = static$uninitialized;
isolate$current.Duration$DartSECONDS_PER_DAY$field = static$uninitialized;
isolate$current.Duration$DartMINUTES_PER_DAY$field = static$uninitialized;
}
);
RunEntry(unnamedd9297f$main$member, this.arguments ? (this.arguments.slice ? [].concat(this.arguments.slice()) : this.arguments) : []);
$
而且大小helloworld.dart.app.js是102k！
在优化模式下运行时，它生成以下 javascript -helloworld.dart.js大小为 20k
$ cat helloworld.dart.js
var e;function f(a,b){if(b>=0&&b<a.length)return b;h(i(b))};var j={},k={};function aa(a,b,c){if(b)a.g=function(){return b.call(c)}}function ba(a,b,c,d){function g(b,g,t,m){return a.call(c,d,b,g,t,m)}aa(g,b,c);return g}function l(a,b){if(a.prototype.__proto__)a.prototype.__proto__=b.prototype;else{var c=function(){};c.prototype=b.prototype;a.prototype=new c;a.prototype.constructor=a}}function ca(a,b){return typeof a=="number"&&typeof b=="number"?a+b:a.na(b)}function da(a){a/=4;return a<0?Math.ceil(a):Math.floor(a)}
function o(a,b){if(a===void 0)return b===void 0;else if(typeof a==typeof b&&typeof a!="object")return a===b;return a.G(b)}function h(a){a&&typeof a=="object"&&Error.captureStackTrace&&Error.captureStackTrace(a);throw a;}function p(){var a=new q;a.f=s("ya",ea);a.va="";a.qa="";a.N=[];h(a)}var u={d:0};
<snapped>
y.push(function(){x.fb=j;x.eb=j;x.gb=j});y.push(function(){x.Ta=j;x.Sa=j;x.Ra=j;x.Wa=j;x.Va=j;x.Ua=j});(function(a,b){if(!A){var c=new ya;oa=c;sa(c,function(){a(b)});Ea();x=c}})(function(){return qb()(1,u,"Hello world!")},this.arguments?this.arguments.slice?[].concat(this.arguments.slice()):this.arguments:[]);
$
为什么 dart 编译器生成的 javascript 代码如此庞大？
他们试图通过生成如此庞大的 javascript 文件来解决什么问题？
旁注：javascript文件太大了，所以抛出了以下错误：
哎呀！您的问题无法提交，因为：正文限制为 30000 个字符；你输入了 140984