JSFiddle - React, Tailwind, and code Playground

HTML

<div id="content"></div>

JavaScript

function gtz(val) {
  return val >= 0;
}

function print(val) {
    $('<p>').text(val).appendTo($('#content'));
}

print( gtz(1) );
print( gtz("1") );
print( gtz(false) );
print( gtz(true) );
print( gtz(undefined) );
print( gtz(null) );
print( gtz({}) );
print( gtz([]) );
print( gtz("") );