C++ V8 8.2的使用

       ​V8是一个的开源的JS和WASM引擎，用C++编写,NODE就是基于V8搞的，这些背景知识就不多说了。项目中，需要对一部分动态的规则逻辑放在体外配置，并且业务的规则是需要有逻辑控制的，这里用V8是再合适不过了。目前网上找到的资料和实例，在V8版本差异下有些许不同，这里就8.2给出正确示例。

/// 执行脚本.
v8::Local CompileRun(const char *js) {
    v8::Local result;
    MaybeLocal source =String::NewFromUtf8(v8::Isolate::GetCurrent(), js).ToLocalChecked();
    v8::TryCatch tryCatch(v8::Isolate::GetCurrent());
    auto context = v8::Isolate::GetCurrent()->GetCurrentContext();
    auto script = v8::Script::Compile(context, source.ToLocalChecked());
    script.ToLocalChecked()->Run(context).ToLocal(&result);
    return result;
}

int main(int argc, char *argv[]) {
    
    /// 要执行的脚本.
    const char *Script="JSON.stringify({'a':1});";

    /// 返回的json字符串.
    string resultStr;

    /// 初始化V8.
    v8::V8::InitializeICUDefaultLocation("");
    v8::V8::InitializeExternalStartupData("");
    platform = v8::platform::NewDefaultPlatform();
    v8::V8::InitializePlatform(platform.get());
    v8::V8::Initialize();

    v8::Isolate::CreateParams create_params;
    create_params.array_buffer_allocator = v8::ArrayBuffer::Allocator::NewDefaultAllocator();
    v8::Isolate *isolate = v8::Isolate::New(create_params);
    {
        v8::Isolate::Scope isolate_scope(isolate);
        v8::HandleScope scope(isolate);
        v8::Local context = v8::Context::New(isolate);
        {
            v8::Context::Scope context_scope(context);
            v8::Local result = CompileRun(Script);
            if (!result.IsEmpty()) {
                v8::String::Utf8Value utf8(isolate, result);
                resultStr = string(*utf8);
            }
        }
    }

    printf("ret: %sn", resultStr.data());

    isolate->Dispose();

    delete create_params.array_buffer_allocator;
}