I have 2 arrays of keywords. I need to figure out the index of the first keyword in array 1 that matches any of the keywords in array 2.
Examples
array1 = ['spinach', 'avocado', 'milk', 'beans', 'ham', 'eggs', 'cheese'];
array2 = ['cheese', 'milk'];
In this example, milk at index 2 would be the first match, and I want to return the index of 2.
Can I use array.find() to return the index of the first match, if each element is compared to array2 using regex?
You could use Array#findIndex and check the second array with Array#includes.
var array1 = ['spinach', 'avocado', 'milk', 'beans', 'ham', 'eggs', 'cheese'],
array2 = ['cheese', 'milk'];
console.log(array1.findIndex(v => array2.includes(v)));You can find matching index using findIndex() and includes():
let index = array1.findIndex(s => array2.includes(s));
Demo:
let a1 = ['spinach', 'avocado', 'milk', 'beans', 'ham', 'eggs', 'cheese'],
a2 = ['cheese', 'milk'];
let index = a1.findIndex(s => a2.includes(s));
console.log(index);Docs:
Use .findIndex instead:
const array1 = ['spinach', 'avocado', 'milk', 'beans', 'ham', 'eggs', 'cheese'];
const array2 = ['cheese', 'milk'];
const foundIndex = array1.findIndex(elm => array2.includes(elm));
console.log(foundIndex);
You could create a regular expression from array2 and then use Array.findIndex:
var re = new RegExp('^'+array2.join('|')+'$');
var found = array1.findIndex(function (e) { return re.test(e); });
