index.js
function merge (a, b) {
  for (var k in b)
    a[k] = a[k] || b[k]
}
function merge (a, b) {
  for (var k in b)
    a[k] = a[k] || b[k]
}
function merge ( a , b ) { for ( var k in b ) a [ k ] = a [ k ] || b [ k ] }
the first line is header, in JSON format, with no whitespace.
the first line is header in JSON format with no whitespace .