blob: 05fe8d3c8ec6b1b1f98a342baa523bab9345566a [file] [log] [blame]
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;