Proposal for temporary scope variables

thinArrow.js

//Proposal for temporary scope variables

let result = something.crazy.long.bar ? something.crazy.long.bar() : something.crazy.long.other();

//with() - Not 'strict' compliant
with (something.crazy.long){
  result = bar ? bar() : other();
}

//fat arrow function
result = (a => a.bar ? a.bar() : a.other())(something.crazy.long);

//extra variable
let a = something.crazy.long;
let result = a.bar ? a.bar() : a.other();

//cleanest, but pollutes namespace, so...
let result;
{
  let a = something.crazy.long;
  result = a.bar ? a.bar() : a.other();
}

//proposal
//scope good only for a single statement, variable names can't be defined
let result = something.crazy.long -> _1.bar ? _1.bar() : _1.other();

//To avoid implicit variables, another option:
let result = something.crazy.long{label} label.bar ? label.bar() : label.other();

//result of expression temporarily stored
//old
let result = (someArr.length * 20 > 40) && someArr.length * 20;

//var store
let result;
{
  let temp = someArr.length * 20;
  result = temp > 40 && temp;
}

//proposal
//idea: implicitly return var if -> returns true
let result = (someArr.legnth * 20) -> (_1 > 40);