javascript utility functions

gistfile1.txt

// function _pad()
//
// pads the input with count numbers of char characters. Examples:
//   _pad( "7" )         => "7"
//   _pad( "A", 4 )      => "   A"
//   _pad( "7", 4, "*" ) => "***7"

function _pad( input, count, char ) {
  count = count ? count : 0;
  return String( Array( count ).join( ( char ? char : ' ' ) ) + input ).slice( - count );
}

// function _hex_pad()
//
// returns a hex string from a number, padded with count zeros.
//   _hex_pad( 12, 4 ) => "000C"

function _hex_pad( input, count ) {
  return _pad( input.toString(16), count, '0' ).toUpperCase();
}