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- import _xReduce from "./internal/_xReduce.js";
- import _xwrap from "./internal/_xwrap.js";
- import curryN from "./curryN.js";
- /**
- * Initializes a transducer using supplied iterator function. Returns a single
- * item by iterating through the list, successively calling the transformed
- * iterator function and passing it an accumulator value and the current value
- * from the array, and then passing the result to the next call.
- *
- * The iterator function receives two values: *(acc, value)*. It will be
- * wrapped as a transformer to initialize the transducer. A transformer can be
- * passed directly in place of an iterator function. In both cases, iteration
- * may be stopped early with the [`R.reduced`](#reduced) function.
- *
- * A transducer is a function that accepts a transformer and returns a
- * transformer and can be composed directly.
- *
- * A transformer is an object that provides a 2-arity reducing iterator
- * function, step, 0-arity initial value function, init, and 1-arity result
- * extraction function, result. The step function is used as the iterator
- * function in reduce. The result function is used to convert the final
- * accumulator into the return type and in most cases is
- * [`R.identity`](#identity). The init function can be used to provide an
- * initial accumulator, but is ignored by transduce.
- *
- * The iteration is performed with [`R.reduce`](#reduce) after initializing the transducer.
- *
- * @func
- * @memberOf R
- * @since v0.12.0
- * @category List
- * @sig (c -> c) -> ((a, b) -> a) -> a -> [b] -> a
- * @param {Function} xf The transducer function. Receives a transformer and returns a transformer.
- * @param {Function} fn The iterator function. Receives two values, the accumulator and the
- * current element from the array. Wrapped as transformer, if necessary, and used to
- * initialize the transducer
- * @param {*} acc The initial accumulator value.
- * @param {Array} list The list to iterate over.
- * @return {*} The final, accumulated value.
- * @see R.reduce, R.reduced, R.into
- * @example
- *
- * const numbers = [1, 2, 3, 4];
- * const transducer = R.compose(R.map(R.add(1)), R.take(2));
- * R.transduce(transducer, R.flip(R.append), [], numbers); //=> [2, 3]
- *
- * const isOdd = (x) => x % 2 !== 0;
- * const firstOddTransducer = R.compose(R.filter(isOdd), R.take(1));
- * R.transduce(firstOddTransducer, R.flip(R.append), [], R.range(0, 100)); //=> [1]
- */
- var transduce =
- /*#__PURE__*/
- curryN(4, function transduce(xf, fn, acc, list) {
- return _xReduce(xf(typeof fn === 'function' ? _xwrap(fn) : fn), acc, list);
- });
- export default transduce;
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