Append or prepend a string to a predefined string

concatStrings.js

var prepend = concatStrings('prependWith-'),
    append = concatStrings('-appendWith', true);
    
console.log(prepend('baseString')); // outputs prependWith-baseString
console.log(append('baseString')); // outputs baseString-appendWith

function concatStrings (classFragmentA, reverse) {
  return function (classFragmentB) {
    var fragments = [classFragmentA, classFragmentB];
    return (reverse) ? fragments.reverse().join('') : fragments.join('');
  };
}