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Justin Sze Wei Teo
9,418 PointschangeColor() comes before its function changeColor() is defined. This is ok?
Hi all,
As per the title, I notice that in this video tutorial, changeColor() is run before function changeColor(){....} is defined.
Why is this possible?
See code extracted from tutorial below,
//When clicking on New Color button $("#revealColorSelect").click(function(){ //Show colorSelect div or hide colorSelect div changeColor(); $("#colorSelect").toggle();
});
//update the new color span function changeColor() { var r = $("#red").val(); var g = $("#green").val(); var b = $("#blue").val();
1 Answer
Steven Parker
229,771 Points
This is an example of "hoisting".
This is a principle of many modern languages where declarations are "virtually raised" to the top of their scope. This allows forward references to function correctly and not generate errors.
Justin Sze Wei Teo
9,418 PointsJustin Sze Wei Teo
9,418 PointsThat helps thanks Steven Parker. Alternatively, is it always safer to declare the function before using it to run?