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var apply = require('./_apply'),    arrayMap = require('./_arrayMap'),    baseIteratee = require('./_baseIteratee'),    baseRest = require('./_baseRest');
/** Error message constants. */var FUNC_ERROR_TEXT = 'Expected a function';
/** * Creates a function that iterates over `pairs` and invokes the corresponding * function of the first predicate to return truthy. The predicate-function * pairs are invoked with the `this` binding and arguments of the created * function. * * @static * @memberOf _ * @since 4.0.0 * @category Util * @param {Array} pairs The predicate-function pairs. * @returns {Function} Returns the new composite function. * @example * * var func = _.cond([ *   [_.matches({ 'a': 1 }),           _.constant('matches A')], *   [_.conforms({ 'b': _.isNumber }), _.constant('matches B')], *   [_.stubTrue,                      _.constant('no match')] * ]); * * func({ 'a': 1, 'b': 2 }); * // => 'matches A' * * func({ 'a': 0, 'b': 1 }); * // => 'matches B' * * func({ 'a': '1', 'b': '2' }); * // => 'no match' */function cond(pairs) {  var length = pairs == null ? 0 : pairs.length,      toIteratee = baseIteratee;
  pairs = !length ? [] : arrayMap(pairs, function(pair) {    if (typeof pair[1] != 'function') {      throw new TypeError(FUNC_ERROR_TEXT);    }    return [toIteratee(pair[0]), pair[1]];  });
  return baseRest(function(args) {    var index = -1;    while (++index < length) {      var pair = pairs[index];      if (apply(pair[0], this, args)) {        return apply(pair[1], this, args);      }    }  });}
module.exports = cond;