How to best access a potentially const variable in a func that is to big for default stack?

[tsojtsoj]

The `const` thing works, I tried it again, the issue is that it takes ages to 
compile. Apparently it would also work when using `let defaultB: B = block:`, 
the first issue I had is that I didn't use `block` but an extra function which 
resulted in program termination (I am not 100% sure that it was a stack 
overflow but like 80-90%). With `block` there isn't a stack overflow, however I 
still can't use `func`because using a global `let` var results in side effect 
issues.