partial.js•1.01 kB
define(['./underscore', './_executeBound', './restArguments'], function (underscore, _executeBound, restArguments) {
// Partially apply a function by creating a version that has had some of its
// arguments pre-filled, without changing its dynamic `this` context. `_` acts
// as a placeholder by default, allowing any combination of arguments to be
// pre-filled. Set `_.partial.placeholder` for a custom placeholder argument.
var partial = restArguments(function(func, boundArgs) {
var placeholder = partial.placeholder;
var bound = function() {
var position = 0, length = boundArgs.length;
var args = Array(length);
for (var i = 0; i < length; i++) {
args[i] = boundArgs[i] === placeholder ? arguments[position++] : boundArgs[i];
}
while (position < arguments.length) args.push(arguments[position++]);
return _executeBound(func, bound, this, this, args);
};
return bound;
});
partial.placeholder = underscore;
return partial;
});