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import _arity from './internal/_arity';import _curry1 from './internal/_curry1';import map from './map';import max from './max';import reduce from './reduce';

/** * 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 = _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;