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Esther AlQaisi
2,311 PointsNot understanding the condition inside the if clause
The condition inside the if clause is supposed to evaluate whether or not the highNumber variable is a number. So, why wouldn't it be something like this...
if ( highNumber == number) { }
?
I don't understand how if ( highNumber ) { }
alone is a condition.
3 Answers
Cameron Childres
11,817 PointsHi Esther,
The magic here comes from two things: parseInt() and truthy/falsy values.
First, parseInt() takes the string given to it from the prompt and converts it to a number value. If it cannot convert it to a number value it returns NaN ('not a number'):
const highNumber = parseInt(inputHigh)
A value being "truthy" means that when it is looked at in a boolean context it is considered to be true. Conveniently for us numbers are "truthy" and NaN is "falsy". So when you have:
if (highNumber) {}
It will either be looking at a number value or NaN -- nothing else will be produced by parseInt(). If it's a number it's true, if it's NaN it's false.
Hope this helps! Let me know if you have any questions.
Esther AlQaisi
2,311 PointsThank you, this is the first time I've heard of truthy/falsy values. I'm going to read up on them a bit more
richard ly
998 PointsThank you. I feel like this was a key concept that wasn't talked about enough in the video