JavaScript: implementare la funzione range() di PHP

In JavaScript possiamo implementare la funzione di PHP che genera un range di valori.

La soluzione è la seguente:

'use strict';

const range = ( low, high, step ) => {
	let matrix = [];
	let inival, endval, plus;
	let walker = step || 1;
	let chars = false;

	if ( !isNaN( low ) && !isNaN( high ) ) {
    	inival = low;
		endval = high;
	} else if ( isNaN( low ) && isNaN( high ) ) {
    	chars = true;
		inival = low.charCodeAt( 0 );
		endval = high.charCodeAt( 0 );
	} else {
    	inival = ( isNaN( low ) ? 0 : low );
		endval = ( isNaN( high ) ? 0 : high );
	}

	plus = ( ( inival > endval ) ? false : true );
    if ( plus ) {
    	while ( inival <= endval ) {
			matrix.push( ( ( chars ) ? String.fromCharCode( inival ) : inival ) );
			inival += walker;
		}
	} else {
    	while ( inival >= endval ) {
			matrix.push( ( ( chars ) ? String.fromCharCode( inival ) : inival ) );
			inival -= walker;
		}
    }

    return matrix;	
};

Esempi:

range( 0, 12 ); // [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ]

range( 0, 100, 10 ); // [ 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 ]

range( 'a', 'i' ); // [ 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i' ]