Chrome Version       : 50.0.2661.94 (64-bit)
URLs (if applicable) : Dev Tools
Other browsers tested:
  Add OK or FAIL, along with the version, after other browsers where you
have tested this issue:
     Safari:
    Firefox:
         IE:

What steps will reproduce the problem?
(1) Open Dev Tools
(2) Go to the Console tab
(3) try the following code:
console.log(foo);
let foo = 1;
It should throw a ReferenceError
(4) ask for foo (declared above)
foo
it throws a RefeenceError, foo isn't defined. In this case, we could say that the whole first action (the log AND the let has been ignored)
(5) Try to declare foo
let foo = 2;
It throws a TypeError, and says that foo HAS already been declared


What is the expected result?
The user should have the chance to declare/define the variable at some point

What happens instead?
After it breaks, the variable is useless in a permanent way

Please provide any additional information below. Attach a screenshot if
possible.