Array

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Array

​MDN​
Test Array
Array.isArray(array)
This does not work to test if its an array.
if (array) {
  // empty arrays evaluate as false
}
​
if (array && array.length > 0) {
  // you may still want to capture the array
}
Clone an array
const clone = array.slice(0);
Iterate keys in an array (for...in)
  const array = ['x', 'y', 'z'];
  for (const key in array) {
    console.log(key);
  }
0
1
2
​https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in​
Iterate values in an array (for...of)
  const array = ['x', 'y', 'z'];
  for (const value of array) {
    console.log(value);
  }
x
y
z
​https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...of​
Appending/merging arrays together
Reuse Array:
array1.push(...array2);
New Array:
const array3 = array1.concat(array2);

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JavaScript

Async & Await / Promises

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Test Array

Clone an array

Iterate keys in an array (for...in)

Iterate values in an array (for...of)

Appending/merging arrays together