HORIZON PROJECT

var baseRest = require('./_baseRest'),

    createWrap = require('./_createWrap'),

    getHolder = require('./_getHolder'),

    replaceHolders = require('./_replaceHolders');

/** Used to compose bitmasks for function metadata. */

var WRAP_PARTIAL_FLAG = 32;

/**

 * Creates a function that invokes `func` with `partials` prepended to the

 * arguments it receives. This method is like `_.bind` except it does **not**

 * alter the `this` binding.

 *

 * The `_.partial.placeholder` value, which defaults to `_` in monolithic

 * builds, may be used as a placeholder for partially applied arguments.

 *

 * **Note:** This method doesn't set the "length" property of partially

 * applied functions.

 *

 * @static

 * @memberOf _

 * @since 0.2.0

 * @category Function

 * @param {Function} func The function to partially apply arguments to.

 * @param {...*} [partials] The arguments to be partially applied.

 * @returns {Function} Returns the new partially applied function.

 * @example

 *

 * function greet(greeting, name) {

 *   return greeting + ' ' + name;

 * }

 *

 * var sayHelloTo = _.partial(greet, 'hello');

 * sayHelloTo('fred');

 * // => 'hello fred'

 *

 * // Partially applied with placeholders.

 * var greetFred = _.partial(greet, _, 'fred');

 * greetFred('hi');

 * // => 'hi fred'

 */

var partial = baseRest(function(func, partials) {

  var holders = replaceHolders(partials, getHolder(partial));

  return createWrap(func, WRAP_PARTIAL_FLAG, undefined, partials, holders);

});

// Assign default placeholders.

partial.placeholder = {};

module.exports = partial;