javascript - loop not working if function name is in a variable when checking if function exists -

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• check if function exists name in string? 2 answers

the below code works if use function name directly , not variable function name.

i make work loop variable having function name.

please !

function func_1() {     alert("function exists"); }  function func_2() {     alert("function exists"); }  var functions = ["func_1", "func_2", "func_3", "func_4"];  (var = 0; < functions.length; i++) {     var func_name = functions[i]; // doesnt work < 1 want work     var func_name = func_3; // works      if (typeof func_name === 'function') {         alert("hello world");     }      alert("iterating well"); } 

according this answer matt, should "check whether it's defined in global scope":

if (typeof window[func_name] === "function") {     alert( '"hello world", says ' + func_name ); }