Created
August 29, 2018 17:50
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// .filter(Boolean) | |
// .fitler to unique values | |
const fruit = ['Apple', 'Banana', 'Apple', 'Orange'] | |
console.log(Array.from(new Set(fruit))) | |
const unique = (element, index, fullArray) => fullArray.indexOf(element) === index | |
console.log(fruit.filter(unique)) | |
/* | |
const prod = false | |
const fruit = [ | |
'Apple', 'Banana', 'Orange', | |
'Pear', 'Peach', | |
prod ? 'Grape' : null | |
].filter(Boolean) | |
console.log(fruit) | |
/* | |
console.log( | |
fruit.reduce((acc, element) => { | |
return `${acc}${element}` | |
}) | |
) | |
const pOnlyFruitCapReduce = fruit.reduce((acc, element) => { | |
if (element.startsWith('P')) { | |
acc.push(element.toUpperCase()) | |
} | |
return acc | |
}, []) | |
console.log(pOnlyFruitCapReduce) | |
const pOnlyFruitCapArray = fruit | |
.filter(element => element.startsWith('P')) | |
.map(element => element.toUpperCase()) | |
console.log(pOnlyFruitCapArray) | |
let pOnlyFruitCap = [] | |
for (let index = 0; index < fruit.length; index++) { | |
const element = fruit[index] | |
if (element.startsWith('P')) { | |
pOnlyFruitCap[pOnlyFruitCap.length] = element.toUpperCase() | |
} | |
} | |
console.log(pOnlyFruitCap) | |
/* | |
let pOnlyFruitWithFilter = fruit.filter(element => element.startsWith('P')) | |
console.log(pOnlyFruitWithFilter) | |
let pOnlyFruit = [] | |
for (let index = 0; index < fruit.length; index++) { | |
const element = fruit[index]; | |
if (element.startsWith('P')) { | |
pOnlyFruit[pOnlyFruit.length] = element | |
} | |
} | |
console.log(pOnlyFruit) | |
*/ | |
/* | |
const allCapsFruitWithMap = fruit.map(element => { | |
return element.toUpperCase() | |
}) | |
console.log(allCapsFruitWithMap) | |
let allCapsFruit = [] | |
for (let index = 0; index < fruit.length; index++) { | |
const element = fruit[index]; | |
allCapsFruit[index] = element.toUpperCase() | |
} | |
console.log(allCapsFruit) | |
console.log(fruit) | |
*/ | |
/* | |
fruit.forEach(element => { | |
console.log(element) | |
}) | |
for (let index = 0; index < fruit.length; index++) { | |
const element = fruit[index]; | |
console.log(element) | |
} | |
*/ | |
// console.log(fruit.reverse()) | |
// console.log(fruit) | |
// let newFruit = [] | |
// for (let index = fruit.length - 1; index >= 0; index--) { | |
// newFruit[newFruit.length] = fruit[index]; | |
// } | |
// for (let index = 0; index < newFruit.length; index++) { | |
// fruit[index] = newFruit[index]; | |
// } | |
// console.log(fruit) | |
/* | |
const obj = {name: 'bob'} | |
const fruit = ['Apple', obj, 'Banana', 'Apple', 'Orange'] | |
console.log(fruit.lastIndexOf('Apple')) | |
let lastIndexOfApple | |
for (let index = fruit.length - 1; index >= 0; index--) { | |
const element = fruit[index]; | |
if (element === 'Apple') { | |
lastIndexOfApple = index | |
break; | |
} | |
} | |
console.log(lastIndexOfApple) | |
console.log(fruit) | |
console.log(fruit.slice(-2)) | |
console.log(fruit.fill(3, 2, 5)) | |
console.log( | |
Array.from({length: 2}, (v, i) => i) | |
) | |
console.log(Array.of(8,3)) | |
console.log(Array.from({'0': 'hi', length: 1})) | |
*/ |
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