In JavaScript, I can check if a string can be evaluated without an actual evaluation?

Question

I am trying to write a function that converts something into a function. The function should work as follows:

• Check if it is already a function, and if so returns it easily.
• Check if this is a string, and if so, then there is a global function with that name, if so returns.
• Check if it is possible to evaluate the string, and if so, return the lambda (anonymous) function that evaluates the string.
• If all previous attempts to convert a value to a function fail, return the lambda (anonymous) function that returns the value. This is also how I handle all other types of variables (numbers, zero, undefined, booleans, objects and arrays).

function canEval(str){
  try { eval(str); } catch (e){ return false; }
  return true;
}
function toFunc(v){
  if(typeof(v) == "function") return v;
  if(typeof(v) == "string"){
    if(
      window[v] != undefined &&
      typeof(window[v]) == "function"
    ) return window[v];
    if(canEval(v))
      return function(){eval(v)};
  }
  return function(){return v;};
};

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Answer 1

- , , . , toFunc, , .

function toFunc(v){
    if(typeof(v) == "function") return v;
    if(typeof(v) == "string"){
      if(
        window[v] != undefined &&
        typeof(window[v]) == "function"
      ) return window[v];
      try {
        return new Function(v);
      }catch(e){}
    }
    return function(){return v;};
  };

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Function try-catch