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- import _arity from "./internal/_arity.js";
- import _curry1 from "./internal/_curry1.js";
- import map from "./map.js";
- import max from "./max.js";
- import reduce from "./reduce.js";
- /**
- * Returns a function, `fn`, which encapsulates `if/else, if/else, ...` logic.
- * `R.cond` takes a list of [predicate, transformer] pairs. All of the arguments
- * to `fn` are applied to each of the predicates in turn until one returns a
- * "truthy" value, at which point `fn` returns the result of applying its
- * arguments to the corresponding transformer. If none of the predicates
- * matches, `fn` returns undefined.
- *
- * @func
- * @memberOf R
- * @since v0.6.0
- * @category Logic
- * @sig [[(*... -> Boolean),(*... -> *)]] -> (*... -> *)
- * @param {Array} pairs A list of [predicate, transformer]
- * @return {Function}
- * @see R.ifElse, R.unless, R.when
- * @example
- *
- * const fn = R.cond([
- * [R.equals(0), R.always('water freezes at 0°C')],
- * [R.equals(100), R.always('water boils at 100°C')],
- * [R.T, temp => 'nothing special happens at ' + temp + '°C']
- * ]);
- * fn(0); //=> 'water freezes at 0°C'
- * fn(50); //=> 'nothing special happens at 50°C'
- * fn(100); //=> 'water boils at 100°C'
- */
-
- var cond =
- /*#__PURE__*/
- _curry1(function cond(pairs) {
- var arity = reduce(max, 0, map(function (pair) {
- return pair[0].length;
- }, pairs));
- return _arity(arity, function () {
- var idx = 0;
-
- while (idx < pairs.length) {
- if (pairs[idx][0].apply(this, arguments)) {
- return pairs[idx][1].apply(this, arguments);
- }
-
- idx += 1;
- }
- });
- });
-
- export default cond;
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