Some Questions about the generated codes

[EhsanAramide]

Hi, dear Vandad!

I have some questions about the dart compilers that I thought this repository would be a great place to speak about it and document for others.

1. As you know in the dart JIT/AOT compiler we can pass definitions via --define=<key>=<value> option. Now my question is the below code snnipts.

// JIT compiler
// $ dart --define=name=ehsan main.dart
var definition = String.fromEnvironment('name');
print(definition); // ehsan

but in AOT compilation value isn't accessible, if the variable type qualifier be var and should be const

// AOT compiler
// $ dart compile exe --define=name=ehsan -o main main.dart; ./main
var definition = String.fromEnvironment('name'); // also `bool.hasEnvironment('name')` returns false
print(definition); // '' empty String, false boolean, 0 int

Actully my question is what happen in generated code that makes this difference in AOT and JIT compilation?

2. Is platform checking will happen in runtime? (in AOT compilation)

// the is<platform> static variables also use this getter
 switch (Platform.operatingSystem) {
   case 'linux':
     // do something linux
     break;
   case 'macos':
     // do something in mac
     break;
   // and so on...
 }

[EhsanAramide]

Hi! In the dart-lang/language repository I found an issue which is related to my question (I think second one). I will put it here ti make it more clear for others and maybe in documentations.

https://github.com/dart-lang/language/issues/1889