if statement with ! before variable

 

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  • What does an exclamation mark before a variable mean in JavaScript 2 answers

    • ! is the plan language equivalent of 'not'. it is the shorthand way of saying if (boolval != true), notice the ! in != also means not as in not equal. So the section of code you posted pretty much just says if the timer is NOT active, activate it.

    The 0 is converted to false before ! logically negates it, producing true.

    if(x) means "if x is true "

    if(!x) means "if not x is true ", which is the same thing as "if x is false "

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