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In JS when the IF condition is null/undefined/0/nan/"" expression, all is interpreted as false, also true

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Boolean expression

An expression with a value of true or false . Non-Boolean expressions can also be converted to a Boolean value if desired, but the following rules are followed:

  • All objects are treated as true.
  • The string is treated as false when and only if the string is empty.
  • null and undefined are treated as false.
  • When and only if the number is zero, the number is treated as false.

In JS when the IF condition is null/undefined/0/nan/"" expression, all is interpreted as false, also true

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