pnpm/lib/node_modules/ramda/dist/ramda.js

Fast, disk space efficient package manager

//  Ramda v0.26.1
//  https://github.com/ramda/ramda
//  (c) 2013-2018 Scott Sauyet, Michael Hurley, and David Chambers
//  Ramda may be freely distributed under the MIT license.

(function (global, factory) {
	typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
	typeof define === 'function' && define.amd ? define(['exports'], factory) :
	(factory((global.R = {})));
}(this, (function (exports) { 'use strict';

/**
 * A function that always returns `false`. Any passed in parameters are ignored.
 *
 * @func
 * @memberOf R
 * @since v0.9.0
 * @category Function
 * @sig * -> Boolean
 * @param {*}
 * @return {Boolean}
 * @see R.T
 * @example
 *
 *      R.F(); //=> false
 */
var F = function() {return false;};

/**
 * A function that always returns `true`. Any passed in parameters are ignored.
 *
 * @func
 * @memberOf R
 * @since v0.9.0
 * @category Function
 * @sig * -> Boolean
 * @param {*}
 * @return {Boolean}
 * @see R.F
 * @example
 *
 *      R.T(); //=> true
 */
var T = function() {return true;};

/**
 * A special placeholder value used to specify "gaps" within curried functions,
 * allowing partial application of any combination of arguments, regardless of
 * their positions.
 *
 * If `g` is a curried ternary function and `_` is `R.__`, the following are
 * equivalent:
 *
 *   - `g(1, 2, 3)`
 *   - `g(_, 2, 3)(1)`
 *   - `g(_, _, 3)(1)(2)`
 *   - `g(_, _, 3)(1, 2)`
 *   - `g(_, 2, _)(1, 3)`
 *   - `g(_, 2)(1)(3)`
 *   - `g(_, 2)(1, 3)`
 *   - `g(_, 2)(_, 3)(1)`
 *
 * @name __
 * @constant
 * @memberOf R
 * @since v0.6.0
 * @category Function
 * @example
 *
 *      const greet = R.replace('{name}', R.__, 'Hello, {name}!');
 *      greet('Alice'); //=> 'Hello, Alice!'
 */
var __ = {'@@functional/placeholder': true};

function _isPlaceholder(a) {
  return a != null &&
         typeof a === 'object' &&
         a['@@functional/placeholder'] === true;
}

/**
 * Optimized internal one-arity curry function.
 *
 * @private
 * @category Function
 * @param {Function} fn The function to curry.
 * @return {Function} The curried function.
 */
function _curry1(fn) {
  return function f1(a) {
    if (arguments.length === 0 || _isPlaceholder(a)) {
      return f1;
    } else {
      return fn.apply(this, arguments);
    }
  };
}

/**
 * Optimized internal two-arity curry function.
 *
 * @private
 * @category Function
 * @param {Function} fn The function to curry.
 * @return {Function} The curried function.
 */
function _curry2(fn) {
  return function f2(a, b) {
    switch (arguments.length) {
      case 0:
        return f2;
      case 1:
        return _isPlaceholder(a)
          ? f2
          : _curry1(function(_b) { return fn(a, _b); });
      default:
        return _isPlaceholder(a) && _isPlaceholder(b)
          ? f2
          : _isPlaceholder(a)
            ? _curry1(function(_a) { return fn(_a, b); })
            : _isPlaceholder(b)
              ? _curry1(function(_b) { return fn(a, _b); })
              : fn(a, b);
    }
  };
}

/**
 * Adds two values.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category Math
 * @sig Number -> Number -> Number
 * @param {Number} a
 * @param {Number} b
 * @return {Number}
 * @see R.subtract
 * @example
 *
 *      R.add(2, 3);       //=>  5
 *      R.add(7)(10);      //=> 17
 */
var add = _curry2(function add(a, b) {
  return Number(a) + Number(b);
});

/**
 * Private `concat` function to merge two array-like objects.
 *
 * @private
 * @param {Array|Arguments} [set1=[]] An array-like object.
 * @param {Array|Arguments} [set2=[]] An array-like object.
 * @return {Array} A new, merged array.
 * @example
 *
 *      _concat([4, 5, 6], [1, 2, 3]); //=> [4, 5, 6, 1, 2, 3]
 */
function _concat(set1, set2) {
  set1 = set1 || [];
  set2 = set2 || [];
  var idx;
  var len1 = set1.length;
  var len2 = set2.length;
  var result = [];

  idx = 0;
  while (idx < len1) {
    result[result.length] = set1[idx];
    idx += 1;
  }
  idx = 0;
  while (idx < len2) {
    result[result.length] = set2[idx];
    idx += 1;
  }
  return result;
}

function _arity(n, fn) {
  /* eslint-disable no-unused-vars */
  switch (n) {
    case 0: return function() { return fn.apply(this, arguments); };
    case 1: return function(a0) { return fn.apply(this, arguments); };
    case 2: return function(a0, a1) { return fn.apply(this, arguments); };
    case 3: return function(a0, a1, a2) { return fn.apply(this, arguments); };
    case 4: return function(a0, a1, a2, a3) { return fn.apply(this, arguments); };
    case 5: return function(a0, a1, a2, a3, a4) { return fn.apply(this, arguments); };
    case 6: return function(a0, a1, a2, a3, a4, a5) { return fn.apply(this, arguments); };
    case 7: return function(a0, a1, a2, a3, a4, a5, a6) { return fn.apply(this, arguments); };
    case 8: return function(a0, a1, a2, a3, a4, a5, a6, a7) { return fn.apply(this, arguments); };
    case 9: return function(a0, a1, a2, a3, a4, a5, a6, a7, a8) { return fn.apply(this, arguments); };
    case 10: return function(a0, a1, a2, a3, a4, a5, a6, a7, a8, a9) { return fn.apply(this, arguments); };
    default: throw new Error('First argument to _arity must be a non-negative integer no greater than ten');
  }
}

/**
 * Internal curryN function.
 *
 * @private
 * @category Function
 * @param {Number} length The arity of the curried function.
 * @param {Array} received An array of arguments received thus far.
 * @param {Function} fn The function to curry.
 * @return {Function} The curried function.
 */
function _curryN(length, received, fn) {
  return function() {
    var combined = [];
    var argsIdx = 0;
    var left = length;
    var combinedIdx = 0;
    while (combinedIdx < received.length || argsIdx < arguments.length) {
      var result;
      if (combinedIdx < received.length &&
          (!_isPlaceholder(received[combinedIdx]) ||
           argsIdx >= arguments.length)) {
        result = received[combinedIdx];
      } else {
        result = arguments[argsIdx];
        argsIdx += 1;
      }
      combined[combinedIdx] = result;
      if (!_isPlaceholder(result)) {
        left -= 1;
      }
      combinedIdx += 1;
    }
    return left <= 0
      ? fn.apply(this, combined)
      : _arity(left, _curryN(length, combined, fn));
  };
}

/**
 * Returns a curried equivalent of the provided function, with the specified
 * arity. The curried function has two unusual capabilities. First, its
 * arguments needn't be provided one at a time. If `g` is `R.curryN(3, f)`, the
 * following are equivalent:
 *
 *   - `g(1)(2)(3)`
 *   - `g(1)(2, 3)`
 *   - `g(1, 2)(3)`
 *   - `g(1, 2, 3)`
 *
 * Secondly, the special placeholder value [`R.__`](#__) may be used to specify
 * "gaps", allowing partial application of any combination of arguments,
 * regardless of their positions. If `g` is as above and `_` is [`R.__`](#__),
 * the following are equivalent:
 *
 *   - `g(1, 2, 3)`
 *   - `g(_, 2, 3)(1)`
 *   - `g(_, _, 3)(1)(2)`
 *   - `g(_, _, 3)(1, 2)`
 *   - `g(_, 2)(1)(3)`
 *   - `g(_, 2)(1, 3)`
 *   - `g(_, 2)(_, 3)(1)`
 *
 * @func
 * @memberOf R
 * @since v0.5.0
 * @category Function
 * @sig Number -> (* -> a) -> (* -> a)
 * @param {Number} length The arity for the returned function.
 * @param {Function} fn The function to curry.
 * @return {Function} A new, curried function.
 * @see R.curry
 * @example
 *
 *      const sumArgs = (...args) => R.sum(args);
 *
 *      const curriedAddFourNumbers = R.curryN(4, sumArgs);
 *      const f = curriedAddFourNumbers(1, 2);
 *      const g = f(3);
 *      g(4); //=> 10
 */
var curryN = _curry2(function curryN(length, fn) {
  if (length === 1) {
    return _curry1(fn);
  }
  return _arity(length, _curryN(length, [], fn));
});

/**
 * Creates a new list iteration function from an existing one by adding two new
 * parameters to its callback function: the current index, and the entire list.
 *
 * This would turn, for instance, [`R.map`](#map) function into one that
 * more closely resembles `Array.prototype.map`. Note that this will only work
 * for functions in which the iteration callback function is the first
 * parameter, and where the list is the last parameter. (This latter might be
 * unimportant if the list parameter is not used.)
 *
 * @func
 * @memberOf R
 * @since v0.15.0
 * @category Function
 * @category List
 * @sig ((a ... -> b) ... -> [a] -> *) -> ((a ..., Int, [a] -> b) ... -> [a] -> *)
 * @param {Function} fn A list iteration function that does not pass index or list to its callback
 * @return {Function} An altered list iteration function that passes (item, index, list) to its callback
 * @example
 *
 *      const mapIndexed = R.addIndex(R.map);
 *      mapIndexed((val, idx) => idx + '-' + val, ['f', 'o', 'o', 'b', 'a', 'r']);
 *      //=> ['0-f', '1-o', '2-o', '3-b', '4-a', '5-r']
 */
var addIndex = _curry1(function addIndex(fn) {
  return curryN(fn.length, function() {
    var idx = 0;
    var origFn = arguments[0];
    var list = arguments[arguments.length - 1];
    var args = Array.prototype.slice.call(arguments, 0);
    args[0] = function() {
      var result = origFn.apply(this, _concat(arguments, [idx, list]));
      idx += 1;
      return result;
    };
    return fn.apply(this, args);
  });
});

/**
 * Optimized internal three-arity curry function.
 *
 * @private
 * @category Function
 * @param {Function} fn The function to curry.
 * @return {Function} The curried function.
 */
function _curry3(fn) {
  return function f3(a, b, c) {
    switch (arguments.length) {
      case 0:
        return f3;
      case 1:
        return _isPlaceholder(a)
          ? f3
          : _curry2(function(_b, _c) { return fn(a, _b, _c); });
      case 2:
        return _isPlaceholder(a) && _isPlaceholder(b)
          ? f3
          : _isPlaceholder(a)
            ? _curry2(function(_a, _c) { return fn(_a, b, _c); })
            : _isPlaceholder(b)
              ? _curry2(function(_b, _c) { return fn(a, _b, _c); })
              : _curry1(function(_c) { return fn(a, b, _c); });
      default:
        return _isPlaceholder(a) && _isPlaceholder(b) && _isPlaceholder(c)
          ? f3
          : _isPlaceholder(a) && _isPlaceholder(b)
            ? _curry2(function(_a, _b) { return fn(_a, _b, c); })
            : _isPlaceholder(a) && _isPlaceholder(c)
              ? _curry2(function(_a, _c) { return fn(_a, b, _c); })
              : _isPlaceholder(b) && _isPlaceholder(c)
                ? _curry2(function(_b, _c) { return fn(a, _b, _c); })
                : _isPlaceholder(a)
                  ? _curry1(function(_a) { return fn(_a, b, c); })
                  : _isPlaceholder(b)
                    ? _curry1(function(_b) { return fn(a, _b, c); })
                    : _isPlaceholder(c)
                      ? _curry1(function(_c) { return fn(a, b, _c); })
                      : fn(a, b, c);
    }
  };
}

/**
 * Applies a function to the value at the given index of an array, returning a
 * new copy of the array with the element at the given index replaced with the
 * result of the function application.
 *
 * @func
 * @memberOf R
 * @since v0.14.0
 * @category List
 * @sig Number -> (a -> a) -> [a] -> [a]
 * @param {Number} idx The index.
 * @param {Function} fn The function to apply.
 * @param {Array|Arguments} list An array-like object whose value
 *        at the supplied index will be replaced.
 * @return {Array} A copy of the supplied array-like object with
 *         the element at index `idx` replaced with the value
 *         returned by applying `fn` to the existing element.
 * @see R.update
 * @example
 *
 *      R.adjust(1, R.toUpper, ['a', 'b', 'c', 'd']);      //=> ['a', 'B', 'c', 'd']
 *      R.adjust(-1, R.toUpper, ['a', 'b', 'c', 'd']);     //=> ['a', 'b', 'c', 'D']
 * @symb R.adjust(-1, f, [a, b]) = [a, f(b)]
 * @symb R.adjust(0, f, [a, b]) = [f(a), b]
 */
var adjust = _curry3(function adjust(idx, fn, list) {
  if (idx >= list.length || idx < -list.length) {
    return list;
  }
  var start = idx < 0 ? list.length : 0;
  var _idx = start + idx;
  var _list = _concat(list);
  _list[_idx] = fn(list[_idx]);
  return _list;
});

/**
 * Tests whether or not an object is an array.
 *
 * @private
 * @param {*} val The object to test.
 * @return {Boolean} `true` if `val` is an array, `false` otherwise.
 * @example
 *
 *      _isArray([]); //=> true
 *      _isArray(null); //=> false
 *      _isArray({}); //=> false
 */
var _isArray = Array.isArray || function _isArray(val) {
  return (val != null &&
          val.length >= 0 &&
          Object.prototype.toString.call(val) === '[object Array]');
};

function _isTransformer(obj) {
  return obj != null && typeof obj['@@transducer/step'] === 'function';
}

/**
 * Returns a function that dispatches with different strategies based on the
 * object in list position (last argument). If it is an array, executes [fn].
 * Otherwise, if it has a function with one of the given method names, it will
 * execute that function (functor case). Otherwise, if it is a transformer,
 * uses transducer [xf] to return a new transformer (transducer case).
 * Otherwise, it will default to executing [fn].
 *
 * @private
 * @param {Array} methodNames properties to check for a custom implementation
 * @param {Function} xf transducer to initialize if object is transformer
 * @param {Function} fn default ramda implementation
 * @return {Function} A function that dispatches on object in list position
 */
function _dispatchable(methodNames, xf, fn) {
  return function() {
    if (arguments.length === 0) {
      return fn();
    }
    var args = Array.prototype.slice.call(arguments, 0);
    var obj = args.pop();
    if (!_isArray(obj)) {
      var idx = 0;
      while (idx < methodNames.length) {
        if (typeof obj[methodNames[idx]] === 'function') {
          return obj[methodNames[idx]].apply(obj, args);
        }
        idx += 1;
      }
      if (_isTransformer(obj)) {
        var transducer = xf.apply(null, args);
        return transducer(obj);
      }
    }
    return fn.apply(this, arguments);
  };
}

function _reduced(x) {
  return x && x['@@transducer/reduced'] ? x :
    {
      '@@transducer/value': x,
      '@@transducer/reduced': true
    };
}

var _xfBase = {
  init: function() {
    return this.xf['@@transducer/init']();
  },
  result: function(result) {
    return this.xf['@@transducer/result'](result);
  }
};

function XAll(f, xf) {
  this.xf = xf;
  this.f = f;
  this.all = true;
}
XAll.prototype['@@transducer/init'] = _xfBase.init;
XAll.prototype['@@transducer/result'] = function(result) {
  if (this.all) {
    result = this.xf['@@transducer/step'](result, true);
  }
  return this.xf['@@transducer/result'](result);
};
XAll.prototype['@@transducer/step'] = function(result, input) {
  if (!this.f(input)) {
    this.all = false;
    result = _reduced(this.xf['@@transducer/step'](result, false));
  }
  return result;
};

var _xall = _curry2(function _xall(f, xf) { return new XAll(f, xf); });

/**
 * Returns `true` if all elements of the list match the predicate, `false` if
 * there are any that don't.
 *
 * Dispatches to the `all` method of the second argument, if present.
 *
 * Acts as a transducer if a transformer is given in list position.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category List
 * @sig (a -> Boolean) -> [a] -> Boolean
 * @param {Function} fn The predicate function.
 * @param {Array} list The array to consider.
 * @return {Boolean} `true` if the predicate is satisfied by every element, `false`
 *         otherwise.
 * @see R.any, R.none, R.transduce
 * @example
 *
 *      const equals3 = R.equals(3);
 *      R.all(equals3)([3, 3, 3, 3]); //=> true
 *      R.all(equals3)([3, 3, 1, 3]); //=> false
 */
var all = _curry2(_dispatchable(['all'], _xall, function all(fn, list) {
  var idx = 0;
  while (idx < list.length) {
    if (!fn(list[idx])) {
      return false;
    }
    idx += 1;
  }
  return true;
}));

/**
 * Returns the larger of its two arguments.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category Relation
 * @sig Ord a => a -> a -> a
 * @param {*} a
 * @param {*} b
 * @return {*}
 * @see R.maxBy, R.min
 * @example
 *
 *      R.max(789, 123); //=> 789
 *      R.max('a', 'b'); //=> 'b'
 */
var max = _curry2(function max(a, b) { return b > a ? b : a; });

function _map(fn, functor) {
  var idx = 0;
  var len = functor.length;
  var result = Array(len);
  while (idx < len) {
    result[idx] = fn(functor[idx]);
    idx += 1;
  }
  return result;
}

function _isString(x) {
  return Object.prototype.toString.call(x) === '[object String]';
}

/**
 * Tests whether or not an object is similar to an array.
 *
 * @private
 * @category Type
 * @category List
 * @sig * -> Boolean
 * @param {*} x The object to test.
 * @return {Boolean} `true` if `x` has a numeric length property and extreme indices defined; `false` otherwise.
 * @example
 *
 *      _isArrayLike([]); //=> true
 *      _isArrayLike(true); //=> false
 *      _isArrayLike({}); //=> false
 *      _isArrayLike({length: 10}); //=> false
 *      _isArrayLike({0: 'zero', 9: 'nine', length: 10}); //=> true
 */
var _isArrayLike = _curry1(function isArrayLike(x) {
  if (_isArray(x)) { return true; }
  if (!x) { return false; }
  if (typeof x !== 'object') { return false; }
  if (_isString(x)) { return false; }
  if (x.nodeType === 1) { return !!x.length; }
  if (x.length === 0) { return true; }
  if (x.length > 0) {
    return x.hasOwnProperty(0) && x.hasOwnProperty(x.length - 1);
  }
  return false;
});

function XWrap(fn) {
  this.f = fn;
}
XWrap.prototype['@@transducer/init'] = function() {
  throw new Error('init not implemented on XWrap');
};
XWrap.prototype['@@transducer/result'] = function(acc) { return acc; };
XWrap.prototype['@@transducer/step'] = function(acc, x) {
  return this.f(acc, x);
};

function _xwrap(fn) { return new XWrap(fn); }

/**
 * Creates a function that is bound to a context.
 * Note: `R.bind` does not provide the additional argument-binding capabilities of
 * [Function.prototype.bind](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind).
 *
 * @func
 * @memberOf R
 * @since v0.6.0
 * @category Function
 * @category Object
 * @sig (* -> *) -> {*} -> (* -> *)
 * @param {Function} fn The function to bind to context
 * @param {Object} thisObj The context to bind `fn` to
 * @return {Function} A function that will execute in the context of `thisObj`.
 * @see R.partial
 * @example
 *
 *      const log = R.bind(console.log, console);
 *      R.pipe(R.assoc('a', 2), R.tap(log), R.assoc('a', 3))({a: 1}); //=> {a: 3}
 *      // logs {a: 2}
 * @symb R.bind(f, o)(a, b) = f.call(o, a, b)
 */
var bind = _curry2(function bind(fn, thisObj) {
  return _arity(fn.length, function() {
    return fn.apply(thisObj, arguments);
  });
});

function _arrayReduce(xf, acc, list) {
  var idx = 0;
  var len = list.length;
  while (idx < len) {
    acc = xf['@@transducer/step'](acc, list[idx]);
    if (acc && acc['@@transducer/reduced']) {
      acc = acc['@@transducer/value'];
      break;
    }
    idx += 1;
  }
  return xf['@@transducer/result'](acc);
}

function _iterableReduce(xf, acc, iter) {
  var step = iter.next();
  while (!step.done) {
    acc = xf['@@transducer/step'](acc, step.value);
    if (acc && acc['@@transducer/reduced']) {
      acc = acc['@@transducer/value'];
      break;
    }
    step = iter.next();
  }
  return xf['@@transducer/result'](acc);
}

function _methodReduce(xf, acc, obj, methodName) {
  return xf['@@transducer/result'](obj[methodName](bind(xf['@@transducer/step'], xf), acc));
}

var symIterator = (typeof Symbol !== 'undefined') ? Symbol.iterator : '@@iterator';

function _reduce(fn, acc, list) {
  if (typeof fn === 'function') {
    fn = _xwrap(fn);
  }
  if (_isArrayLike(list)) {
    return _arrayReduce(fn, acc, list);
  }
  if (typeof list['fantasy-land/reduce'] === 'function') {
    return _methodReduce(fn, acc, list, 'fantasy-land/reduce');
  }
  if (list[symIterator] != null) {
    return _iterableReduce(fn, acc, list[symIterator]());
  }
  if (typeof list.next === 'function') {
    return _iterableReduce(fn, acc, list);
  }
  if (typeof list.reduce === 'function') {
    return _methodReduce(fn, acc, list, 'reduce');
  }

  throw new TypeError('reduce: list must be array or iterable');
}

function XMap(f, xf) {
  this.xf = xf;
  this.f = f;
}
XMap.prototype['@@transducer/init'] = _xfBase.init;
XMap.prototype['@@transducer/result'] = _xfBase.result;
XMap.prototype['@@transducer/step'] = function(result, input) {
  return this.xf['@@transducer/step'](result, this.f(input));
};

var _xmap = _curry2(function _xmap(f, xf) { return new XMap(f, xf); });

function _has(prop, obj) {
  return Object.prototype.hasOwnProperty.call(obj, prop);
}

var toString = Object.prototype.toString;
var _isArguments = (function() {
  return toString.call(arguments) === '[object Arguments]' ?
    function _isArguments(x) { return toString.call(x) === '[object Arguments]'; } :
    function _isArguments(x) { return _has('callee', x); };
}());

// cover IE < 9 keys issues
var hasEnumBug = !({toString: null}).propertyIsEnumerable('toString');
var nonEnumerableProps = [
  'constructor', 'valueOf', 'isPrototypeOf', 'toString',
  'propertyIsEnumerable', 'hasOwnProperty', 'toLocaleString'
];
// Safari bug
var hasArgsEnumBug = (function() {
  'use strict';
  return arguments.propertyIsEnumerable('length');
}());

var contains = function contains(list, item) {
  var idx = 0;
  while (idx < list.length) {
    if (list[idx] === item) {
      return true;
    }
    idx += 1;
  }
  return false;
};

/**
 * Returns a list containing the names of all the enumerable own properties of
 * the supplied object.
 * Note that the order of the output array is not guaranteed to be consistent
 * across different JS platforms.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category Object
 * @sig {k: v} -> [k]
 * @param {Object} obj The object to extract properties from
 * @return {Array} An array of the object's own properties.
 * @see R.keysIn, R.values
 * @example
 *
 *      R.keys({a: 1, b: 2, c: 3}); //=> ['a', 'b', 'c']
 */
var keys = typeof Object.keys === 'function' && !hasArgsEnumBug ?
  _curry1(function keys(obj) {
    return Object(obj) !== obj ? [] : Object.keys(obj);
  }) :
  _curry1(function keys(obj) {
    if (Object(obj) !== obj) {
      return [];
    }
    var prop, nIdx;
    var ks = [];
    var checkArgsLength = hasArgsEnumBug && _isArguments(obj);
    for (prop in obj) {
      if (_has(prop, obj) && (!checkArgsLength || prop !== 'length')) {
        ks[ks.length] = prop;
      }
    }
    if (hasEnumBug) {
      nIdx = nonEnumerableProps.length - 1;
      while (nIdx >= 0) {
        prop = nonEnumerableProps[nIdx];
        if (_has(prop, obj) && !contains(ks, prop)) {
          ks[ks.length] = prop;
        }
        nIdx -= 1;
      }
    }
    return ks;
  });

/**
 * Takes a function and
 * a [functor](https://github.com/fantasyland/fantasy-land#functor),
 * applies the function to each of the functor's values, and returns
 * a functor of the same shape.
 *
 * Ramda provides suitable `map` implementations for `Array` and `Object`,
 * so this function may be applied to `[1, 2, 3]` or `{x: 1, y: 2, z: 3}`.
 *
 * Dispatches to the `map` method of the second argument, if present.
 *
 * Acts as a transducer if a transformer is given in list position.
 *
 * Also treats functions as functors and will compose them together.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category List
 * @sig Functor f => (a -> b) -> f a -> f b
 * @param {Function} fn The function to be called on every element of the input `list`.
 * @param {Array} list The list to be iterated over.
 * @return {Array} The new list.
 * @see R.transduce, R.addIndex
 * @example
 *
 *      const double = x => x * 2;
 *
 *      R.map(double, [1, 2, 3]); //=> [2, 4, 6]
 *
 *      R.map(double, {x: 1, y: 2, z: 3}); //=> {x: 2, y: 4, z: 6}
 * @symb R.map(f, [a, b]) = [f(a), f(b)]
 * @symb R.map(f, { x: a, y: b }) = { x: f(a), y: f(b) }
 * @symb R.map(f, functor_o) = functor_o.map(f)
 */
var map = _curry2(_dispatchable(['fantasy-land/map', 'map'], _xmap, function map(fn, functor) {
  switch (Object.prototype.toString.call(functor)) {
    case '[object Function]':
      return curryN(functor.length, function() {
        return fn.call(this, functor.apply(this, arguments));
      });
    case '[object Object]':
      return _reduce(function(acc, key) {
        acc[key] = fn(functor[key]);
        return acc;
      }, {}, keys(functor));
    default:
      return _map(fn, functor);
  }
}));

/**
 * Retrieve the value at a given path.
 *
 * @func
 * @memberOf R
 * @since v0.2.0
 * @category Object
 * @typedefn Idx = String | Int
 * @sig [Idx] -> {a} -> a | Undefined
 * @param {Array} path The path to use.
 * @param {Object} obj The object to retrieve the nested property from.
 * @return {*} The data at `path`.
 * @see R.prop
 * @example
 *
 *      R.path(['a', 'b'], {a: {b: 2}}); //=> 2
 *      R.path(['a', 'b'], {c: {b: 2}}); //=> undefined
 */
var path = _curry2(function path(paths, obj) {
  var val = obj;
  var idx = 0;
  while (idx < paths.length) {
    if (val == null) {
      return;
    }
    val = val[paths[idx]];
    idx += 1;
  }
  return val;
});

/**
 * Returns a function that when supplied an object returns the indicated
 * property of that object, if it exists.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category Object
 * @sig s -> {s: a} -> a | Undefined
 * @param {String} p The property name
 * @param {Object} obj The object to query
 * @return {*} The value at `obj.p`.
 * @see R.path
 * @example
 *
 *      R.prop('x', {x: 100}); //=> 100
 *      R.prop('x', {}); //=> undefined
 *      R.compose(R.inc, R.prop('x'))({ x: 3 }) //=> 4
 */

var prop = _curry2(function prop(p, obj) { return path([p], obj); });

/**
 * Returns a new list by plucking the same named property off all objects in
 * the list supplied.
 *
 * `pluck` will work on
 * any [functor](https://github.com/fantasyland/fantasy-land#functor) in
 * addition to arrays, as it is equivalent to `R.map(R.prop(k), f)`.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category List
 * @sig Functor f => k -> f {k: v} -> f v
 * @param {Number|String} key The key name to pluck off of each object.
 * @param {Array} f The array or functor to consider.
 * @return {Array} The list of values for the given key.
 * @see R.props
 * @example
 *
 *      var getAges = R.pluck('age');
 *      getAges([{name: 'fred', age: 29}, {name: 'wilma', age: 27}]); //=> [29, 27]
 *
 *      R.pluck(0, [[1, 2], [3, 4]]);               //=> [1, 3]
 *      R.pluck('val', {a: {val: 3}, b: {val: 5}}); //=> {a: 3, b: 5}
 * @symb R.pluck('x', [{x: 1, y: 2}, {x: 3, y: 4}, {x: 5, y: 6}]) = [1, 3, 5]
 * @symb R.pluck(0, [[1, 2], [3, 4], [5, 6]]) = [1, 3, 5]
 */
var pluck = _curry2(function pluck(p, list) {
  return map(prop(p), list);
});

/**
 * Returns a single item by iterating through the list, successively calling
 * the 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 may use
 * [`R.reduced`](#reduced) to shortcut the iteration.
 *
 * The arguments' order of [`reduceRight`](#reduceRight)'s iterator function
 * is *(value, acc)*.
 *
 * Note: `R.reduce` does not skip deleted or unassigned indices (sparse
 * arrays), unlike the native `Array.prototype.reduce` method. For more details
 * on this behavior, see:
 * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/reduce#Description
 *
 * Dispatches to the `reduce` method of the third argument, if present. When
 * doing so, it is up to the user to handle the [`R.reduced`](#reduced)
 * shortcuting, as this is not implemented by `reduce`.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category List
 * @sig ((a, b) -> a) -> a -> [b] -> a
 * @param {Function} fn The iterator function. Receives two values, the accumulator and the
 *        current element from the array.
 * @param {*} acc The accumulator value.
 * @param {Array} list The list to iterate over.
 * @return {*} The final, accumulated value.
 * @see R.reduced, R.addIndex, R.reduceRight
 * @example
 *
 *      R.reduce(R.subtract, 0, [1, 2, 3, 4]) // => ((((0 - 1) - 2) - 3) - 4) = -10
 *      //          -               -10
 *      //         / \              / \
 *      //        -   4           -6   4
 *      //       / \              / \
 *      //      -   3   ==>     -3   3
 *      //     / \              / \
 *      //    -   2           -1   2
 *      //   / \              / \
 *      //  0   1            0   1
 *
 * @symb R.reduce(f, a, [b, c, d]) = f(f(f(a, b), c), d)
 */
var reduce = _curry3(_reduce);

/**
 * Takes a list of predicates and returns a predicate that returns true for a
 * given list of arguments if every one of the provided predicates is satisfied
 * by those arguments.
 *
 * The function returned is a curried function whose arity matches that of the
 * highest-arity predicate.
 *
 * @func
 * @memberOf R
 * @since v0.9.0
 * @category Logic
 * @sig [(*... -> Boolean)] -> (*... -> Boolean)
 * @param {Array} predicates An array of predicates to check
 * @return {Function} The combined predicate
 * @see R.anyPass
 * @example
 *
 *      const isQueen = R.propEq('rank', 'Q');
 *      const isSpade = R.propEq('suit', '♠︎');
 *      const isQueenOfSpades = R.allPass([isQueen, isSpade]);
 *
 *      isQueenOfSpades({rank: 'Q', suit: '♣︎'}); //=> false
 *      isQueenOfSpades({rank: 'Q', suit: '♠︎'}); //=> true
 */
var allPass = _curry1(function allPass(preds) {
  return curryN(reduce(max, 0, pluck('length', preds)), function() {
    var idx = 0;
    var len = preds.length;
    while (idx < len) {
      if (!preds[idx].apply(this, arguments)) {
        return false;
      }
      idx += 1;
    }
    return true;
  });
});

/**
 * Returns a function that always returns the given value. Note that for
 * non-primitives the value returned is a reference to the original value.
 *
 * This function is known as `const`, `constant`, or `K` (for K combinator) in
 * other languages and libraries.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category Function
 * @sig a -> (* -> a)
 * @param {*} val The value to wrap in a function
 * @return {Function} A Function :: * -> val.
 * @example
 *
 *      const t = R.always('Tee');
 *      t(); //=> 'Tee'
 */
var always = _curry1(function always(val) {
  return function() {
    return val;
  };
});

/**
 * Returns `true` if both arguments are `true`; `false` otherwise.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category Logic
 * @sig a -> b -> a | b
 * @param {Any} a
 * @param {Any} b
 * @return {Any} the first argument if it is falsy, otherwise the second argument.
 * @see R.both
 * @example
 *
 *      R.and(true, true); //=> true
 *      R.and(true, false); //=> false
 *      R.and(false, true); //=> false
 *      R.and(false, false); //=> false
 */
var and = _curry2(function and(a, b) {
  return a && b;
});

function XAny(f, xf) {
  this.xf = xf;
  this.f = f;
  this.any = false;
}
XAny.prototype['@@transducer/init'] = _xfBase.init;
XAny.prototype['@@transducer/result'] = function(result) {
  if (!this.any) {
    result = this.xf['@@transducer/step'](result, false);
  }
  return this.xf['@@transducer/result'](result);
};
XAny.prototype['@@transducer/step'] = function(result, input) {
  if (this.f(input)) {
    this.any = true;
    result = _reduced(this.xf['@@transducer/step'](result, true));
  }
  return result;
};

var _xany = _curry2(function _xany(f, xf) { return new XAny(f, xf); });

/**
 * Returns `true` if at least one of the elements of the list match the predicate,
 * `false` otherwise.
 *
 * Dispatches to the `any` method of the second argument, if present.
 *
 * Acts as a transducer if a transformer is given in list position.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category List
 * @sig (a -> Boolean) -> [a] -> Boolean
 * @param {Function} fn The predicate function.
 * @param {Array} list The array to consider.
 * @return {Boolean} `true` if the predicate is satisfied by at least one element, `false`
 *         otherwise.
 * @see R.all, R.none, R.transduce
 * @example
 *
 *      const lessThan0 = R.flip(R.lt)(0);
 *      const lessThan2 = R.flip(R.lt)(2);
 *      R.any(lessThan0)([1, 2]); //=> false
 *      R.any(lessThan2)([1, 2]); //=> true
 */
var any = _curry2(_dispatchable(['any'], _xany, function any(fn, list) {
  var idx = 0;
  while (idx < list.length) {
    if (fn(list[idx])) {
      return true;
    }
    idx += 1;
  }
  return false;
}));

/**
 * Takes a list of predicates and returns a predicate that returns true for a
 * given list of arguments if at least one of the provided predicates is
 * satisfied by those arguments.
 *
 * The function returned is a curried function whose arity matches that of the
 * highest-arity predicate.
 *
 * @func
 * @memberOf R
 * @since v0.9.0
 * @category Logic
 * @sig [(*... -> Boolean)] -> (*... -> Boolean)
 * @param {Array} predicates An array of predicates to check
 * @return {Function} The combined predicate
 * @see R.allPass
 * @example
 *
 *      const isClub = R.propEq('suit', '♣');
 *      const isSpade = R.propEq('suit', '♠');
 *      const isBlackCard = R.anyPass([isClub, isSpade]);
 *
 *      isBlackCard({rank: '10', suit: '♣'}); //=> true
 *      isBlackCard({rank: 'Q', suit: '♠'}); //=> true
 *      isBlackCard({rank: 'Q', suit: '♦'}); //=> false
 */
var anyPass = _curry1(function anyPass(preds) {
  return curryN(reduce(max, 0, pluck('length', preds)), function() {
    var idx = 0;
    var len = preds.length;
    while (idx < len) {
      if (preds[idx].apply(this, arguments)) {
        return true;
      }
      idx += 1;
    }
    return false;
  });
});

/**
 * ap applies a list of functions to a list of values.
 *
 * Dispatches to the `ap` method of the second argument, if present. Also
 * treats curried functions as applicatives.
 *
 * @func
 * @memberOf R
 * @since v0.3.0
 * @category Function
 * @sig [a -> b] -> [a] -> [b]
 * @sig Apply f => f (a -> b) -> f a -> f b
 * @sig (r -> a -> b) -> (r -> a) -> (r -> b)
 * @param {*} applyF
 * @param {*} applyX
 * @return {*}
 * @example
 *
 *      R.ap([R.multiply(2), R.add(3)], [1,2,3]); //=> [2, 4, 6, 4, 5, 6]
 *      R.ap([R.concat('tasty '), R.toUpper], ['pizza', 'salad']); //=> ["tasty pizza", "tasty salad", "PIZZA", "SALAD"]
 *
 *      // R.ap can also be used as S combinator
 *      // when only two functions are passed
 *      R.ap(R.concat, R.toUpper)('Ramda') //=> 'RamdaRAMDA'
 * @symb R.ap([f, g], [a, b]) = [f(a), f(b), g(a), g(b)]
 */
var ap = _curry2(function ap(applyF, applyX) {
  return (
    typeof applyX['fantasy-land/ap'] === 'function'
      ? applyX['fantasy-land/ap'](applyF)
      : typeof applyF.ap === 'function'
        ? applyF.ap(applyX)
        : typeof applyF === 'function'
          ? function(x) { return applyF(x)(applyX(x)); }
          : _reduce(function(acc, f) { return _concat(acc, map(f, applyX)); }, [], applyF)
  );
});

function _aperture(n, list) {
  var idx = 0;
  var limit = list.length - (n - 1);
  var acc = new Array(limit >= 0 ? limit : 0);
  while (idx < limit) {
    acc[idx] = Array.prototype.slice.call(list, idx, idx + n);
    idx += 1;
  }
  return acc;
}

function XAperture(n, xf) {
  this.xf = xf;
  this.pos = 0;
  this.full = false;
  this.acc = new Array(n);
}
XAperture.prototype['@@transducer/init'] = _xfBase.init;
XAperture.prototype['@@transducer/result'] = function(result) {
  this.acc = null;
  return this.xf['@@transducer/result'](result);
};
XAperture.prototype['@@transducer/step'] = function(result, input) {
  this.store(input);
  return this.full ? this.xf['@@transducer/step'](result, this.getCopy()) : result;
};
XAperture.prototype.store = function(input) {
  this.acc[this.pos] = input;
  this.pos += 1;
  if (this.pos === this.acc.length) {
    this.pos = 0;
    this.full = true;
  }
};
XAperture.prototype.getCopy = function() {
  return _concat(Array.prototype.slice.call(this.acc, this.pos),
    Array.prototype.slice.call(this.acc, 0, this.pos)
  );
};

var _xaperture = _curry2(function _xaperture(n, xf) { return new XAperture(n, xf); });

/**
 * Returns a new list, composed of n-tuples of consecutive elements. If `n` is
 * greater than the length of the list, an empty list is returned.
 *
 * Acts as a transducer if a transformer is given in list position.
 *
 * @func
 * @memberOf R
 * @since v0.12.0
 * @category List
 * @sig Number -> [a] -> [[a]]
 * @param {Number} n The size of the tuples to create
 * @param {Array} list The list to split into `n`-length tuples
 * @return {Array} The resulting list of `n`-length tuples
 * @see R.transduce
 * @example
 *
 *      R.aperture(2, [1, 2, 3, 4, 5]); //=> [[1, 2], [2, 3], [3, 4], [4, 5]]
 *      R.aperture(3, [1, 2, 3, 4, 5]); //=> [[1, 2, 3], [2, 3, 4], [3, 4, 5]]
 *      R.aperture(7, [1, 2, 3, 4, 5]); //=> []
 */
var aperture = _curry2(_dispatchable([], _xaperture, _aperture));

/**
 * Returns a new list containing the contents of the given list, followed by
 * the given element.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category List
 * @sig a -> [a] -> [a]
 * @param {*} el The element to add to the end of the new list.
 * @param {Array} list The list of elements to add a new item to.
 *        list.
 * @return {Array} A new list containing the elements of the old list followed by `el`.
 * @see R.prepend
 * @example
 *
 *      R.append('tests', ['write', 'more']); //=> ['write', 'more', 'tests']
 *      R.append('tests', []); //=> ['tests']
 *      R.append(['tests'], ['write', 'more']); //=> ['write', 'more', ['tests']]
 */
var append = _curry2(function append(el, list) {
  return _concat(list, [el]);
});

/**
 * Applies function `fn` to the argument list `args`. This is useful for
 * creating a fixed-arity function from a variadic function. `fn` should be a
 * bound function if context is significant.
 *
 * @func
 * @memberOf R
 * @since v0.7.0
 * @category Function
 * @sig (*... -> a) -> [*] -> a
 * @param {Function} fn The function which will be called with `args`
 * @param {Array} args The arguments to call `fn` with
 * @return {*} result The result, equivalent to `fn(...args)`
 * @see R.call, R.unapply
 * @example
 *
 *      const nums = [1, 2, 3, -99, 42, 6, 7];
 *      R.apply(Math.max, nums); //=> 42
 * @symb R.apply(f, [a, b, c]) = f(a, b, c)
 */
var apply = _curry2(function apply(fn, args) {
  return fn.apply(this, args);
});

/**
 * Returns a list of all the enumerable own properties of the supplied object.
 * Note that the order of the output array is not guaranteed across different
 * JS platforms.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category Object
 * @sig {k: v} -> [v]
 * @param {Object} obj The object to extract values from
 * @return {Array} An array of the values of the object's own properties.
 * @see R.valuesIn, R.keys
 * @example
 *
 *      R.values({a: 1, b: 2, c: 3}); //=> [1, 2, 3]
 */
var values = _curry1(function values(obj) {
  var props = keys(obj);
  var len = props.length;
  var vals = [];
  var idx = 0;
  while (idx < len) {
    vals[idx] = obj[props[idx]];
    idx += 1;
  }
  return vals;
});

// Use custom mapValues function to avoid issues with specs that include a "map" key and R.map
// delegating calls to .map
function mapValues(fn, obj) {
  return keys(obj).reduce(function(acc, key) {
    acc[key] = fn(obj[key]);
    return acc;
  }, {});
}

/**
 * Given a spec object recursively mapping properties to functions, creates a
 * function producing an object of the same structure, by mapping each property
 * to the result of calling its associated function with the supplied arguments.
 *
 * @func
 * @memberOf R
 * @since v0.20.0
 * @category Function
 * @sig {k: ((a, b, ..., m) -> v)} -> ((a, b, ..., m) -> {k: v})
 * @param {Object} spec an object recursively mapping properties to functions for
 *        producing the values for these properties.
 * @return {Function} A function that returns an object of the same structure
 * as `spec', with each property set to the value returned by calling its
 * associated function with the supplied arguments.
 * @see R.converge, R.juxt
 * @example
 *
 *      const getMetrics = R.applySpec({
 *        sum: R.add,
 *        nested: { mul: R.multiply }
 *      });
 *      getMetrics(2, 4); // => { sum: 6, nested: { mul: 8 } }
 * @symb R.applySpec({ x: f, y: { z: g } })(a, b) = { x: f(a, b), y: { z: g(a, b) } }
 */
var applySpec = _curry1(function applySpec(spec) {
  spec = mapValues(
    function(v) { return typeof v == 'function' ? v : applySpec(v); },
    spec
  );

  return curryN(
    reduce(max, 0, pluck('length', values(spec))),
    function() {
      var args = arguments;
      return mapValues(function(f) { return apply(f, args); }, spec);
    });
});

/**
 * Takes a value and applies a function to it.
 *
 * This function is also known as the `thrush` combinator.
 *
 * @func
 * @memberOf R
 * @since v0.25.0
 * @category Function
 * @sig a -> (a -> b) -> b
 * @param {*} x The value
 * @param {Function} f The function to apply
 * @return {*} The result of applying `f` to `x`
 * @example
 *
 *      const t42 = R.applyTo(42);
 *      t42(R.identity); //=> 42
 *      t42(R.add(1)); //=> 43
 */
var applyTo = _curry2(function applyTo(x, f) { return f(x); });

/**
 * Makes an ascending comparator function out of a function that returns a value
 * that can be compared with `<` and `>`.
 *
 * @func
 * @memberOf R
 * @since v0.23.0
 * @category Function
 * @sig Ord b => (a -> b) -> a -> a -> Number
 * @param {Function} fn A function of arity one that returns a value that can be compared
 * @param {*} a The first item to be compared.
 * @param {*} b The second item to be compared.
 * @return {Number} `-1` if fn(a) < fn(b), `1` if fn(b) < fn(a), otherwise `0`
 * @see R.descend
 * @example
 *
 *      const byAge = R.ascend(R.prop('age'));
 *      const people = [
 *        { name: 'Emma', age: 70 },
 *        { name: 'Peter', age: 78 },
 *        { name: 'Mikhail', age: 62 },
 *      ];
 *      const peopleByYoungestFirst = R.sort(byAge, people);
 *        //=> [{ name: 'Mikhail', age: 62 },{ name: 'Emma', age: 70 }, { name: 'Peter', age: 78 }]
 */
var ascend = _curry3(function ascend(fn, a, b) {
  var aa = fn(a);
  var bb = fn(b);
  return aa < bb ? -1 : aa > bb ? 1 : 0;
});

/**
 * Makes a shallow clone of an object, setting or overriding the specified
 * property with the given value. Note that this copies and flattens prototype
 * properties onto the new object as well. All non-primitive properties are
 * copied by reference.
 *
 * @func
 * @memberOf R
 * @since v0.8.0
 * @category Object
 * @sig String -> a -> {k: v} -> {k: v}
 * @param {String} prop The property name to set
 * @param {*} val The new value
 * @param {Object} obj The object to clone
 * @return {Object} A new object equivalent to the original except for the changed property.
 * @see R.dissoc, R.pick
 * @example
 *
 *      R.assoc('c', 3, {a: 1, b: 2}); //=> {a: 1, b: 2, c: 3}
 */
var assoc = _curry3(function assoc(prop, val, obj) {
  var result = {};
  for (var p in obj) {
    result[p] = obj[p];
  }
  result[prop] = val;
  return result;
});

/**
 * Determine if the passed argument is an integer.
 *
 * @private
 * @param {*} n
 * @category Type
 * @return {Boolean}
 */
var _isInteger = Number.isInteger || function _isInteger(n) {
  return (n << 0) === n;
};

/**
 * Checks if the input value is `null` or `undefined`.
 *
 * @func
 * @memberOf R
 * @since v0.9.0
 * @category Type
 * @sig * -> Boolean
 * @param {*} x The value to test.
 * @return {Boolean} `true` if `x` is `undefined` or `null`, otherwise `false`.
 * @example
 *
 *      R.isNil(null); //=> true
 *      R.isNil(undefined); //=> true
 *      R.isNil(0); //=> false
 *      R.isNil([]); //=> false
 */
var isNil = _curry1(function isNil(x) { return x == null; });

/**
 * Makes a shallow clone of an object, setting or overriding the nodes required
 * to create the given path, and placing the specific value at the tail end of
 * that path. Note that this copies and flattens prototype properties onto the
 * new object as well. All non-primitive properties are copied by reference.
 *
 * @func
 * @memberOf R
 * @since v0.8.0
 * @category Object
 * @typedefn Idx = String | Int
 * @sig [Idx] -> a -> {a} -> {a}
 * @param {Array} path the path to set
 * @param {*} val The new value
 * @param {Object} obj The object to clone
 * @return {Object} A new object equivalent to the original except along the specified path.
 * @see R.dissocPath
 * @example
 *
 *      R.assocPath(['a', 'b', 'c'], 42, {a: {b: {c: 0}}}); //=> {a: {b: {c: 42}}}
 *
 *      // Any missing or non-object keys in path will be overridden
 *      R.assocPath(['a', 'b', 'c'], 42, {a: 5}); //=> {a: {b: {c: 42}}}
 */
var assocPath = _curry3(function assocPath(path, val, obj) {
  if (path.length === 0) {
    return val;
  }
  var idx = path[0];
  if (path.length > 1) {
    var nextObj = (!isNil(obj) && _has(idx, obj)) ? obj[idx] : _isInteger(path[1]) ? [] : {};
    val = assocPath(Array.prototype.slice.call(path, 1), val, nextObj);
  }
  if (_isInteger(idx) && _isArray(obj)) {
    var arr = [].concat(obj);
    arr[idx] = val;
    return arr;
  } else {
    return assoc(idx, val, obj);
  }
});

/**
 * Wraps a function of any arity (including nullary) in a function that accepts
 * exactly `n` parameters. Any extraneous parameters will not be passed to the
 * supplied function.
 *
 * @func
 * @memberOf R
 * @since v0.1.0
 * @category Function
 * @sig Number -> (* -> a) -> (* -> a)
 * @param {Number} n The desired arity of the new function.
 * @param {Function} fn The function to wrap.
 * @return {Function} A new function wrapping `fn`. The new function is guaranteed to be of
 *         arity `n`.
 * @see R.binary, R.unary
 * @example
 *
 *      const takesTwoArgs = (a, b) => [a, b];
 *
 *      takesTwoArgs.length; //=> 2
 *      takesTwoArgs(1, 2); //=> [1, 2]
 *
 *      const takesOneArg = R.nAry(1, takesTwoArgs);
 *      takesOneArg.length; //=> 1
 *      // Only `n` arguments are passed to the wrapped function
 *      takesOneArg(1, 2); //=> [1, undefined]
 * @symb R.nAry(0, f)(a, b) = f()
 * @symb R.nAry(1, f)(a, b) = f(a)
 * @symb R.nAry(2, f)(a, b) = f(a, b)
 */
var nAry = _curry2(function nAry(n, fn) {
  switch (n) {
    case 0: return function() {return fn.call(this);};
    case 1: return function(a0) {return fn.call(this, a0);};
    case 2: return function(a0, a1) {return fn.call(this, a0, a1);};
    case 3: return function(a0, a1, a2) {return fn.call(this, a0, a1, a2);};
    case 4: return function(a0, a1, a2, a3) {return fn.call(this, a0, a1, a2, a3);};
    case 5: return function(a0, a1, a2, a3, a4) {return fn.call(this, a0, a1, a2, a3, a4);};
    case 6: return function(a0, a1, a2, a3, a4, a5) {return fn.call(this, a0, a1, a2, a3, a4, a5);};
    case 7: return function(a0, a1, a2, a3, a4, a5, a6) {return fn.call(this, a0, a1, a2, a3, a4, a5, a6);};
    case 8: return function(a0, a1, a2, a3, a4, a5, a6, a7) {return fn.call(this, a0, a1, a2, a3, a4, a5, a6, a7);};
    case 9: return function(a0, a1, a2, a3, a4, a5, a6, a7, a8) {return fn.call(this, a0, a1, a2, a3, a4, a5, a6, a7, a8);};
    case 10: return function(a0, a1, a2, a3, a4, a5, a6, a7, a8, a9) {return fn.call(this, a0, a1, a2, a3, a4, a5, a6, a7, a8, a9);};
    default: throw new Error('First argument to nAry must be a non-negative integer no greater than ten');
  }
});

/**
 * Wraps a function of any arity (including nullary) in a function that accepts
 * exactly 2 parameters. Any extraneous parameters will not be passed to the
 * supplied function.
 *
 * @func
 * @memberOf R
 * @since v0.2.0
 * @category Function
 * @sig (* -> c) -> (a, b -> c)
 * @param {Function} fn The function to wrap.
 * @return {Function} A new function wrapping `fn`. The new function is guaranteed to be of
 *         arity 2.
 * @see R.nAry, R.unary
 * @example
 *
 *      const takesThreeArgs = function(a, b, c) {
 *        return [a, b, c];
 *      };
 *      takesThreeArgs.length; //=> 3
 *      takesThreeArgs(1, 2, 3); //=> [1, 2, 3]
 *
 *      const takesTwoArgs = R.binary(takesThreeArgs);
 *      takesTwoArgs.length; //=> 2
 *      // Only 2 arguments are passed to the wrapped function
 *      takesTwoArgs(1, 2, 3); //=> [1, 2, undefined]
 * @symb R.binary(f)(a, b, c) = f(a, b)
 */
var binary = _curry1(function binary(fn) {
  return nAry(2, fn);
});

function _isFunction(x) {
  return Object.prototype.toString.call(x) === '[object Function]';
}

/**
 * "lifts" a function to be the specified arity, so that it may "map over" that
 * many lists, Functions or other objects that satisfy the [FantasyLand Apply spec](https://github.com/fantasyland/fantasy-land#apply).
 *
 * @func
 * @memberOf R
 * @since v0.7.0
 * @category Function
 * @sig Number -> (*... -> *) -> ([*]... -> [*])
 * @param {Function} fn The function to lift into higher context
 * @return {Function} The lifted function.
 * @see R.lift, R.ap
 * @example
 *
 *      const madd3 = R.liftN(3, (...args) => R.sum(args));
 *      madd3([1,2,3], [1,2,3], [1]); //=> [3, 4, 5, 4, 5, 6, 5, 6, 7]
 */
var liftN = _curry2(function liftN(arity, fn) {
  var lifted = curryN(arity, fn);
  return curryN(arity, function() {
    return _reduce(ap, map(lifted, arguments[0]), Array.prototype.slice.call(arguments, 1));
  });
});

/**
 * "lifts" a function of arity > 1 so that it may "map over" a list, Function or other
 * object that satisfies the [FantasyLand Apply spec](https://github.com/fantasyland/fantasy-land#apply).
 *
 * @func
 * @memberOf R
 * @since v0.7.0
 * @category Function
 * @sig (*... -> *) -> ([*]... -> [*])
 * @param {Function} fn The function to lift into higher context
 * @return {Function} The