var arr = Array(100).fill({name: 'abc'});
arr[9] = {name: 'def'};
var ind;


function find__for (arr, aim) {
  for (let i=0; i<arr.length; i++) {
    if (arr[i].name === aim) {
      return i;
    }
  }
}
function find__findIndex (arr, aim) {
  return arr.findIndex(r => r.name === aim)
}
function find__map_indexOf (arr, aim) {
  return arr.map(e => e.name).indexOf(aim);
}
function find__reduce (arr, aim) {
  return arr.reduce((i, item, index) => item.name === aim ? index : i, -1);
}
function find__some (arr, aim) {
    var j = -1;
    var result = arr.some((obj, i) => { 
        j++;
        return obj.name === aim;
    })
    if (!result) return -1;
    return j;
}