Create new scope in javascript

scope.js

function func() {
  for (var i = 0; i < 10; i++) {
    setTimeout(function() {
      console.log('i:' + i);
    }, 0);
  }
}
// func();
function solution1() {
  for (let i = 0; i < 10; i++) {
    setTimeout(function() {
      console.log('i:' + i);
    }, 0);
  }
}
// solution1();

function solution2() {
  for (var i = 0; i < 10; i++) {
    var fn = function(index){ console.log('i:' + index);};
    setTimeout(fn.bind(null, i), 0);
  }
}
// solution2();


function solution3() {
  for (var i = 0; i < 10; i++) {
    var fn = function(index){ console.log('i:' + index);};
    (function(index) {
      setTimeout(() => {fn(index);}, 0);
    })(i);
  }
}
// solution3();


function solution4() {
  for (var i = 0; i < 10; i++) {
    try {
      throw i;
    } catch(index) {
      setTimeout(function() {
        console.log('i:' + index);
      }, 0);  } 
    }
}
// solution4();

function solution5() {
  for (var i = 0; i < 10; i++) {
    var fn = function(index){ console.log('i:' + index);};
    setTimeout(fn, 0, i);
  }
}

//  solution5();

var solution6fn = function (index){ console.log('i:' + index);};
function solution6() {
  for (var i = 0; i < 10; i++) {
    setTimeout("solution6fn(" + i + ")", 0);
  }
}

 //solution6();