Let expression problem

General Usage
5

I think the subtlety here is that:

let x = ...

behaves differently than

let
  x = ...

For example:

julia> let
         x = 1
         let x = 2
           x = 3
         end
         @show x
       end
x = 1
1

julia> let
         x = 1
         let 
           x = 2
           x = 3
         end
         @show x
       end
x = 3
3

The same issue is discussed in Variable declarations within let blocks

I actually don’t think the manual is very clear on this topic: Scope of Variables · The Julia Language

In particular, it says

An assignment modifies an existing value location, and let creates new locations. This difference is usually not important, and is only detectable in the case of variables that outlive their scope via closures.

I think something like the answer from Variable declarations within let blocks would be a good addition to that section of the manual.

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