fastpad/index.js

Fastest pad left implementation, 2 millions ops in 48ms.

var s = ''; 
var xC;
var txtC = '';

module.exports = pad;

function pad(x,n,txt) {
n-=txt.length+2;
	if(txtC!=txt) txtC = txt;
	var ln = x.length * n;
	if(xC!==x){
		xC = x;
		s = '';
	}

    while(s.length<n) { 
        if (n & 1) s += x; 
        n >>= 1; 
        if (!n) break;
			s += s; 
    } 
    return s+txtC;
}