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- import chain from "./chain.js";
- import compose from "./compose.js";
- import map from "./map.js";
- /**
- * Returns the right-to-left Kleisli composition of the provided functions,
- * each of which must return a value of a type supported by [`chain`](#chain).
- *
- * `R.composeK(h, g, f)` is equivalent to `R.compose(R.chain(h), R.chain(g), f)`.
- *
- * @func
- * @memberOf R
- * @since v0.16.0
- * @category Function
- * @sig Chain m => ((y -> m z), (x -> m y), ..., (a -> m b)) -> (a -> m z)
- * @param {...Function} ...functions The functions to compose
- * @return {Function}
- * @see R.pipeK
- * @deprecated since v0.26.0
- * @example
- *
- * // get :: String -> Object -> Maybe *
- * const get = R.curry((propName, obj) => Maybe(obj[propName]))
- *
- * // getStateCode :: Maybe String -> Maybe String
- * const getStateCode = R.composeK(
- * R.compose(Maybe.of, R.toUpper),
- * get('state'),
- * get('address'),
- * get('user'),
- * );
- * getStateCode({"user":{"address":{"state":"ny"}}}); //=> Maybe.Just("NY")
- * getStateCode({}); //=> Maybe.Nothing()
- * @symb R.composeK(f, g, h)(a) = R.chain(f, R.chain(g, h(a)))
- */
-
- export default function composeK() {
- if (arguments.length === 0) {
- throw new Error('composeK requires at least one argument');
- }
-
- var init = Array.prototype.slice.call(arguments);
- var last = init.pop();
- return compose(compose.apply(this, map(chain, init)), last);
- }
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