bigspin.js

#!/usr/bin/env node

var ESC = '\u001b';
var CSI = ESC + '[';

var L0 = ['        ', ' #      ', '    #   ', '       #'];
var L1 = ['        ', '  #     ', '    #   ', '      # '];
var L2 = ['        ', '   #    ', '    #   ', '     #  '];
var L3 = [' ###### ', '    #   ', '    #   ', '    #   '];
var L4 = ['        ', '     #  ', '    #   ', '   #    '];
var L5 = ['        ', '      # ', '    #   ', '  #     '];
var L6 = ['        ', '       #', '    #   ', ' #      '];

var L = [ L0, L1, L2, L3, L4, L5, L6 ];

function
w(s)
{
        process.stdout.write(s);
}

function
wl(n)
{
        for (var i = 0; i < L.length; i++) {
                w(L[i][n] + '\n');
        }
}

var FIRST = true;
var ITER = 0;

setInterval(function () {
        if (!FIRST) {
                /*
                 * Rewind to the top line of the spinner region.
		 */
		w(CSI + (L.length) + 'A');
		w(CSI + '1G');
        } else {
		FIRST = false;
	}
	wl(ITER++ % L[0].length);
}, 250);