How to check if a variable is not null?

They are not equivalent. The first will execute the block following the if statement if myVar is truthy (i.e. evaluates to true in a conditional), while the second will execute the block if myVar is any value other than null.

The only values that are not truthy in JavaScript are the following (a.k.a. falsy values):

  • null
  • undefined
  • 0
  • "" (the empty string)
  • false
  • NaN

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