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JavaScript JavaScript Array Iteration Methods Combining Array Methods Combining filter() and reduce()

Posted by gerardo keys
gerardo keys
14,292 Points

Not understanding the .filter and .reduce here.

.reduce((highest, product) => { if (highest.price > product.price)

If highest is the accumulator in this function what is it starting at? In the if statement you have if(highest.price > product.price) ... I'm really having trouble understanding what highest.price is supposed to be or represent. How is it finding the highest price?

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

When "reduce" has only one argument (the callback function), the accumulator starts as the first item from the array. Since in the video example, it is chained on a "filter" call, it would be the first item returned by "filter".

Since each element in the array is an object with a "price" property, "highest.price" is the price value of the item determined to be largest.

gerardo keys
gerardo keys
14,292 Points

Omg ty, thats exactly what I was wondering!! You cleared it up perfect!