How to recursively print the alphabet in Javascript?-CodePudding

Seen some solutions using a regular for loop, but was interested in the recursive way

maybe we can define the arr as the alphabet

let arr = ['abcdefghij(...rest_of_alphabet)`]

found this on the interwebs, would this work?

Call map() using the array [ ‘a’, ‘b’, ‘c’ ] Create a new array that holds the result of calling fn(‘a’) Return [ ‘A’ ].concat( map([ ‘b’, ‘c’ ]) ) Repeat steps 1 through 3 with [ ‘b’, ‘c’ ] Repeat steps 1 through 3 for [ ‘c’ ] Eventually, we call map() with an empty array, which ends the recursion.

CodePudding user response：

Here is a way:

const alphabet = Array.from({length: 26}, (x, i) => String.fromCharCode(97   i));

function printEach(arr) {
  if (arr.length === 0) return; // If arr is empty, return
  console.log(arr.shift());     // Remove the first letter from arr and print it
  return printEach(arr);        // Deal with the remaining elements
}

printEach(alphabet);

CodePudding user response：

A simplification of this answer, without the array:

function printAlphabet (codePoint = 97) {
  if (codePoint > 122) return; // If code point is greater than "z"
  console.log(String.fromCodePoint(codePoint));
  return printAlphabet(codePoint   1);
}

printAlphabet();