Language:
js

Source:
function func() {
   for (let i = 0; i < 5; ++i) {
       console.log(i)
   }
   console.log('_______')
   console.log(i)
}
func()

Errors:
1507834084/source.js:6
   console.log(i)
               ^

ReferenceError: i is not defined
   at func (1507834084/source.js:6:17)
   at Object.<anonymous> (1507834084/source.js:8:1)
   at Module._compile (module.js:652:30)
   at Object.Module._extensions..js (module.js:663:10)
   at Module.load (module.js:565:32)
   at tryModuleLoad (module.js:505:12)
   at Function.Module._load (module.js:497:3)
   at Function.Module.runMain (module.js:693:10)
   at startup (bootstrap_node.js:188:16)
   at bootstrap_node.js:609:3

Result:
0
1
2
3
4
_______

let
var

Language:
js

Source:
function func() {
   for (var i = 0; i < 5; ++i) {
       console.log(i)
   }
   console.log('_______')
   console.log(i)
}
func()

Result:
0
1
2
3
4
_______
5