Merge objects within array dynamically

Question

I was unable to reproduce the merge as this popular answer: How can I merge properties of two JavaScript objects dynamically?. However, I do not see my situation as significantly different than the OP. For illustration's sake, here is my data structure:

var tempList1 = [
   {'manager':'John', 'x1':0, 'y1':0, 'x2':1, 'y2':1},
   {'manager':'Julie', 'x1':0, 'y1':0, 'x2':1, 'y2':1},
...
];

var tempList2 = [
   {'manager':'John', 'x3':0, 'y3':0, 'x4':1, 'y4':1},
   {'manager':'Julie', 'x3':0, 'y3':0, 'x4':1, 'y4':1},
...
];

The desired result after merge is:

var combinedList = [
    {'manager':'John', 'x1':0, 'y1':0, 'x2':1, 'y2':1, 'x3':0, 'y3':0, 'x4':1, 'y4':1},
    {'manager':'Julie', 'x1':0, 'y1':0, 'x2':1, 'y2':1, 'x3':0, 'y3':0, 'x4':1, 'y4':1}
];

My attempt was:

          var combinedList = [];
          for (var k = 0; k < managerList.length; k++)
              let merged = {...tempList1[k],...tempList2[k]}
              combinedList.push(merged);

              console.log(combinedList)

But that gave me the error:

Uncaught SyntaxError: Lexical declaration cannot appear in a single-statement context

Question

How should I adjust my code so I can combine each object in my array (as seen above)?