CODEWITHSUNDEEP
javascriptboolean
user8838577
user8838577

Reputation:

javascript Boolean() function is not working correctly

Consider the following snippet of code

   if(word.startsWith("bool"))
   {
        s = word.split(" ");
        return s+" "+ Boolean(s[1]);
   }

Examples

word ="bool 12>3" ==> true

word ="bool 1>3" ==> false

for queries such as bool 1>2 function says true. but if I use it in console, it says the correct answer.

Upvotes: 1

Views: 527

Answers (1)

Barmar
Barmar

Reputation: 781004

Boolean() simply performs type conversion, it doesn't evaluate code. When converting a string to boolean, an empty string becomes false, a non-empty string becomes true.

If you want to evaluate the word, you have to call eval().

return s+" "+ Boolean(eval(s[1]));

Note that using eval() can be dangerous if the data comes from an untrusted source, since this will be able to execute any JavaScript functions.

When you type Boolean(1>3) in the console, 1>3 is evaluated as an expression by the console, it's not a string. To see the same problem in the console, enter Boolean("1>3"), since word is a string, not an expression that has already been evaluated.

Upvotes: 2

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