Complex destructing assignments make wrong code

[LunaBorowska]

This returns 1 (properly):

a = {}
[a.b] = [1, 2, 3]
console.log a.b

This is generated code:

(function() {
  var a;
  a = {};
  a.b = [1, 2, 3][0];
  console.log(a.b);
}).call(this);

This returns undefined:

a = {}
[(a).b] = [1, 2, 3]
console.log a.b

And generated code:

(function() {
  var a, _base;
  a = {};
  // _base.b? Shouldn't it be 0?
  (_base = a).b = [1, 2, 3][_base.b];
  console.log(a.b);
}).call(this);

It seems to work in REPL, but it doesn't in other places.

[vendethiel]

[a.b] = [1, 2, 3]

[jashkenas]

That first example looks correct to me, but the second one was certainly a bug. Should be fixed now.