“Truthy” and “Falsy”
The idea that an if statement expects a “yes” or “no” question as its argument is only partially correct. What would happen if you use something other than a “yes” or “no” question, as in Listing 7.11? Try it out in the console.
Listing 7.11 When if Meets a String
> if ('true') { console.log('"true" is true'); } "true" is true> if ('false') { console.log('"false" is true(?)'); } "false" is true(?)
How did 'false' become true? Many programming languages have a notion of “truthiness,” which means a value in any data type is either “truthy” or “falsy.” The truthiness of a value is determined by what is returned when that value is coerced to a Boolean, either true or false. Each programming ...
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