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Coding filter() function with plain JavaScript


Coding filter() function with plain JavaScript

The filter() method creates a new array with all elements that pass the test implemented by the provided function.

const juice = ["🧃🍏", "🧃🍎", "🍏", "🍎", "🍐", "🍊", "🧃🍐", "🧃🍊"]
const checkIfJuice = item => item.includes("🧃")
const isJuice = juice.filter(checkIfJuice)

isJuice // [ '🧃🍏', '🧃🍎', '🧃🍐', '🧃🍊' ]

Coding filter() function with plain JavaScript

const juice = ["🧃🍏", "🧃🍎", "🍏", "🍎", "🍐", "🍊", "🧃🍐", "🧃🍊"]
const checkIfJuice = item => item.includes("🧃")

const isJuice = newFilter(juice, checkIfJuice)

function newFilter(arr, conditionFunc) {
    const filteredArr = []
    for(let i = 0; i < arr.length; i++) {
        conditionFunc(arr[i]) && filteredArr.push(arr[i])
    }
    return filteredArr
}

isJuice // [ '🧃🍏', '🧃🍎', '🧃🍐', '🧃🍊' ]
© 2021, Andrew Losseff