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Paola Ledesma
2,453 PointsHi there! I was wondering if there is any reason why we need to add || 4 in the 3rd line of the .js doco. Thanks heaps!
var num = num || 4
2 Answers
simhub
26,543 PointsHi Paola,
the || symbol means OR.
var num = num || 4 // If no number passed in, default to 4
the "num" variable will first look for a "num" parameter to be set "function random_number(num){...}" if it isn't set then it will set the num variable "var num = ..." equal 4.
Because the computer will say - hey! you wrote "var num =..." that means you're declaring a variable name "num". Oh! and you want me too set it equal to "4" if there is no parameter "num" set in the "random_number(num)" function.
Paola Ledesma
2,453 Pointssimhub , thanks a lot! Does this mean that "4" is an arbitrary default value that could be changed?
simhub
26,543 PointsYep! :)