I'm learning programming with JavaScript, and I just don't know what's happening here:
let myVar = ('Hello','World!');
console.log(myVar);
The output is:
World!
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If you meant for it to be an array, you need to use square brackets `[]` instead. – John Montgomery Sep 26 '19 at 00:40
2 Answers
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The comma operator evaluates each of its operands (from left to right) and returns the value of the last operand.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Comma_Operator
This means that the expression 'Hello','World!' evaluates to 'World!'
spender
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One more thing to note: JavaScript doesn't use parentheses to as the literal syntax for any type of collection, so putting parentheses around that just ensures that it will be grouped as a single expression. – jirassimok Sep 26 '19 at 00:38
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You're setting the variable to the string "Hello", then setting it to "World". The same thing happens if you set a list of variables inside a parenthetical.
const myVar = (1,2,3,4,5,6);
console.log(myVar);
//6
Where as I think what you were trying to do was use a grouping operator like +.
const myVar = ("Hello, " + "World")
console.log(myVar)
//"Hello, World"
technicallynick
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