Just a short implementation of curry and compose.

functional.js

var _ = (function() {

  var _ = {
    curry: curry,
    compose: compose
  };

  return _;

  function realArgumentCount(unreal, args) {
    var count = 0;
    for (var i = 0; i < args.length; i++) {
      if (args[i] !== unreal) {
        count++;
      }
    }
    return count;
  }

  function merge(unreal, args1, args2) {
    var args = [];
    for (var f=0, i=0; f < args1.length || i < args2.length; f++) {
      if (args1[f] !== unreal && f < args1.length) {
        args.push(args1[f]);
      } else {
        args.push(args2[i++]);
      }
    }
    return args;
  }

  function curry(fn) {
    return function func() {
      var args = new Array(arguments.length);
      for (var i=0;i<arguments.length;i++){args[i]=arguments[i];}
      
      if (realArgumentCount(_, args) < fn.length) {
        return function inner(){
          var innerArgs = new Array(arguments.length);
          for (var i=0;i<arguments.length;i++){innerArgs[i]=arguments[i];}
          
          return func.apply(this, merge(_, args, innerArgs));
        }
      } else {
        return fn.apply(this, args);
      }
    }
  }

  function compose() {
    var fns = new Array(arguments.length);
    for (var i=0;i<arguments.length;i++){fns[i]=arguments[i];}
    return function(value) {
      for (var i = 0; i < fns.length; i++) {
        // expect(fns[i]).to.be.a('function');
        value = fns[i].call(this, value);
      }
      return value;
    };
  }

})();