function curry(func, arity, guard) {
      arity = guard ? undefined : arity;
      var result = createWrap(func, WRAP_CURRY_FLAG, undefined, undefined, undefined, undefined, undefined, arity);
      result.placeholder = curry.placeholder;
      return result;
    }
Creates a function that accepts arguments of `func` and either invokes
`func` returning its result, if at least `arity` number of arguments have
been provided, or returns a function that accepts the remaining `func`
arguments, and so on. The arity of `func` may be specified if `func.length`
is not sufficient.

The `_.curry.placeholder` value, which defaults to `_` in monolithic builds,
may be used as a placeholder for provided arguments.

**Note:** This method doesn't set the "length" property of curried functions.

@static
@memberOf _
@since 2.0.0
@category Function
@param {Function} func The function to curry.
@param {number} [arity=func.length] The arity of `func`.
@param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
@returns {Function} Returns the new curried function.
@example

var abc = function(a, b, c) {
  return [a, b, c];
};

var curried = _.curry(abc);

curried(1)(2)(3);
// => [1, 2, 3]

curried(1, 2)(3);
// => [1, 2, 3]

curried(1, 2, 3);
// => [1, 2, 3]

// Curried with placeholders.
curried(1)(_, 3)(2);
// => [1, 2, 3]