How do I know if it is a single-line block


#1

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I used the arrow function inside of the .filter() method, but I don’t know why it doesn’t work. I feel like I have misunderstood about concepts of single-line block.


#2
 > const r = [375, 20, 3.14, 7, 13, 852]
<- undefined
 > const smallNumbers = r.filter(x => x < 250)
<- undefined
 > smallNumbers
<- > (4) [20, 3.14, 7, 13]

Refresh

 > const r = [375, 20, 3.14, 7, 13, 852]
<- undefined
 > const smallNumbers = r.filter(x => x < 250;)
 x Uncaught SyntaxError: missing ) after argument list
 > 

The semi-colon is the errant token.