Braintree (the payment processor company) uses Rust to speed up batch processing and also fro small command-line utilities they use internally.

Comment a single line:

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Comment multiple lines:

/* 
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const isEven = num => num % 2 === 0

This function can be used like this:

isEven(14)   // true
isEven(21)   // false
isEven(1.4)  // false

Try this function:

const isOdd = num => num % 2 == 1

Use it like this:

isOdd(3)    // true
isOdd(2)    // false
isOdd(1.4)  // false

You can determine if a number is even with the following:

number % 2 == 0
// true means the number is even
// false means the number is odd