Accessing data in a closure?

[Henrique_Becker]

You are looking at the Developer’s Documentation, not the User’s Manual.

Accessing captured variables as fields in a closure object is an implementation detail, we have word of god on this:

@StefanKarpinski

100% with one caveat: accessing the fields of a closure is not technically a stable part of the language’s API, so if you need to access the a field then you should use the explicit struct approach since that is guaranteed to work no matter what changes are made to the compiler. If you don’t need to access the a field then it’s just a matter of preference.