code: function partialAny(fn /* arguments */) {
      var appliedArgs = Array.prototype.slice.call(arguments, 1);
      if ( appliedArgs.length < 1 ) return fn;
  
      return function () {
        var args = _.deepClone(appliedArgs);
        var partialArgs = _.toArray(arguments);
        for (var i=0; i < args.length; i++) {
          if ( args[i] === _ )
            args[i] = partialArgs.shift();
        }
        return fn.apply(this, args.concat(partialArgs));
      };
    }
docs: use _ as a placeholder, and bind non placeholder arguments to fn When the new function is invoked, apply the passed arguments into the placeholders