48 lines
2.0 KiB
JavaScript
48 lines
2.0 KiB
JavaScript
import _curry3 from "./internal/_curry3.js";
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import map from "./map.js";
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import sequence from "./sequence.js";
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/**
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* Maps an [Applicative](https://github.com/fantasyland/fantasy-land#applicative)-returning
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* function over a [Traversable](https://github.com/fantasyland/fantasy-land#traversable),
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* then uses [`sequence`](#sequence) to transform the resulting Traversable of Applicative
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* into an Applicative of Traversable.
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*
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* Dispatches to the `traverse` method of the third argument, if present.
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*
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* @func
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* @memberOf R
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* @since v0.19.0
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* @category List
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* @sig fantasy-land/of :: TypeRep f => f ~> a -> f a
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* @sig (Applicative f, Traversable t) => TypeRep f -> (a -> f b) -> t a -> f (t b)
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* @sig (Applicative f, Traversable t) => (b -> f b) -> (a -> f b) -> t a -> f (t b)
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* @param {Object|Function} TypeRepresentative with an `of` or `fantasy-land/of` method
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* @param {Function} f
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* @param {*} traversable
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* @return {*}
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* @see R.sequence
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* @example
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*
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* // Returns `Maybe.Nothing` if the given divisor is `0`
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* const safeDiv = n => d => d === 0 ? Maybe.Nothing() : Maybe.Just(n / d)
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*
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* R.traverse(Maybe.of, safeDiv(10), [2, 4, 5]); //=> Maybe.Just([5, 2.5, 2])
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* R.traverse(Maybe.of, safeDiv(10), [2, 0, 5]); //=> Maybe.Nothing
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*
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* // Using a Type Representative
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* R.traverse(Maybe, safeDiv(10), Right(4)); //=> Just(Right(2.5))
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* R.traverse(Maybe, safeDiv(10), Right(0)); //=> Nothing
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* R.traverse(Maybe, safeDiv(10), Left("X")); //=> Just(Left("X"))
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*/
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var traverse =
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/*#__PURE__*/
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_curry3(function traverse(F, f, traversable) {
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var of = typeof F['fantasy-land/of'] === 'function' ? F['fantasy-land/of'] : typeof F.of === 'function' ? F.of : F;
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var TypeRep = {
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'fantasy-land/of': of
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};
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return typeof traversable['fantasy-land/traverse'] === 'function' ? traversable['fantasy-land/traverse'](TypeRep, f) : typeof traversable.traverse === 'function' ? traversable.traverse(TypeRep, f) : sequence(TypeRep, map(f, traversable));
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});
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export default traverse; |