The initial problem stems from a line of code that ensures the variable "numbers" is always an array containing the values 1, 2, 3, and 4. This setup causes the condition for an empty array to never be met, making it necessary to remove that line.
Another issue arises from an unnecessary semicolon that subtly alters the logic of the program.
The current logic functions in a way that if "numbers" refers to an array created using the array literal syntax ([]), it will execute an empty statement, followed by a block that returns zero outside of the else-if block.
else if ( numbers === []);{
return 0
}
For checking if an object is an array, use Array.isArray(foo).
To determine if an array is empty, you can check its length (if(myArray.length === 0) ...)
The corrected code you might have intended to write is:
else if (numbers.length === 0) {
return 0
}
However, it appears that the code using "reduce" will function correctly even for arrays of zero length, rendering that logic unnecessary.
What you should aim for is something like this:
function sumArray(numbers) {
if (!numbers) return 0;
return numbers.reduce((a,b) => a + b, 0);
}
console.log(sumArray())
console.log(sumArray([]))
console.log(sumArray([1, 2, 3, 4]))