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Alternative forms[edit]


false +‎ -y


falsy (not comparable)

  1. (programming) Evaluating to false in a Boolean context.
    Antonym: truthy
    • 2012, David Flanagan, JavaScript Pocket Reference, page 40:
      In JavaScript, any expression or statement that expects a boolean value will work with a truthy or falsy value, so the fact that && does not always evaluate to true or false does not cause practical problems.
    • 2014, Basarat Syed, Beginning Node.js, →ISBN, page 33:
      However, in the second case, both '0' and the empty string ('') are falsy (in other words, they behave like false) and are therefore equal with respect to ==.
    • 2016, Kenny Ballou, Learning Elixir, →ISBN, page 92:
      If the first operand (which comes before the question mark--doIt, in this example) is truthy, the expression evaluates to the second operand (between the question mark and colon), and if it's falsy, it evaluates to the third operand (after the colon).