allStarCodeChallenge18.js

/* 

Create a function that accepts a string and a single character, and returns an integer of the count of occurrences the 2nd argument is found in the first one.

If no occurrences can be found, a count of 0 should be returned.

("Hello", "o")  ==>  1
("Hello", "l")  ==>  2
("", "z")       ==>  0
str_count("Hello", 'o'); // returns 1
str_count("Hello", 'l'); // returns 2
str_count("", 'z'); // returns 0

*/

function strCount(str, letter){  
    return str.split('').filter(x => x === letter).length
  }