[julia-users] Do `let` blocks enable compiler optimization of "local" variables?

[Cristóvão Duarte Sousa]

According to the performace tips, code must be inside functions and 
variable must be local for better optimization.

In IJulia notebook I usually put critical code inside dummy functions, 
something like

function f()
    # variables and code here
end
f()

I wonder if doing the visually nicer

let
    # variables and code here
end

would provide the same benefits?