falseyとは 意味・読み方・使い方

形容詞

falsey (not comparable)

1. Alternative form of falsy
   • 2010, Charles Wyke-Smith, Scriptin' with JavaScript and Ajax: A Designer's Guide, ISBN 0132104768, page 44:

     If the variable is set to anything except a falsey value, the test will evaluate to true.

   • 2013, Dan Wellman, Jquery Hotshot, ISBN 1849519110:

     In JavaScript, as well as the true or false Boolean values, other types of variables can be said to be truthy or falsey.

   • 2014, Eric T. Freeman & ‎Elisabeth Robson, Head First JavaScript Programming: A Brain-Friendly Guide, ISBN 1449340113, page 292:

     To remember which values are truthy and which are falsey, just memorize the five falsey values - undefined, null, 0, "" and NaN -- and remember that everything else is truthy.

   • 2015, Daniel Higginbotham, Clojure for the Brave and True, ISBN 1593277237, page 40:

     Clojure uses the Boolean operators or and and. or returns either the first truthy value or the last value, and returns the first falsey value or, if no values are falsey, the last truthy value.