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var LodashWrapper = require('./_LodashWrapper'),    flatRest = require('./_flatRest'),    getData = require('./_getData'),    getFuncName = require('./_getFuncName'),    isArray = require('./isArray'),    isLaziable = require('./_isLaziable');
/** Error message constants. */var FUNC_ERROR_TEXT = 'Expected a function';
/** Used to compose bitmasks for function metadata. */var WRAP_CURRY_FLAG = 8,    WRAP_PARTIAL_FLAG = 32,    WRAP_ARY_FLAG = 128,    WRAP_REARG_FLAG = 256;
/** * Creates a `_.flow` or `_.flowRight` function. * * @private * @param {boolean} [fromRight] Specify iterating from right to left. * @returns {Function} Returns the new flow function. */function createFlow(fromRight) {  return flatRest(function(funcs) {    var length = funcs.length,        index = length,        prereq = LodashWrapper.prototype.thru;
    if (fromRight) {      funcs.reverse();    }    while (index--) {      var func = funcs[index];      if (typeof func != 'function') {        throw new TypeError(FUNC_ERROR_TEXT);      }      if (prereq && !wrapper && getFuncName(func) == 'wrapper') {        var wrapper = new LodashWrapper([], true);      }    }    index = wrapper ? index : length;    while (++index < length) {      func = funcs[index];
      var funcName = getFuncName(func),          data = funcName == 'wrapper' ? getData(func) : undefined;
      if (data && isLaziable(data[0]) &&            data[1] == (WRAP_ARY_FLAG | WRAP_CURRY_FLAG | WRAP_PARTIAL_FLAG | WRAP_REARG_FLAG) &&            !data[4].length && data[9] == 1          ) {        wrapper = wrapper[getFuncName(data[0])].apply(wrapper, data[3]);      } else {        wrapper = (func.length == 1 && isLaziable(func))          ? wrapper[funcName]()          : wrapper.thru(func);      }    }    return function() {      var args = arguments,          value = args[0];
      if (wrapper && args.length == 1 && isArray(value)) {        return wrapper.plant(value).value();      }      var index = 0,          result = length ? funcs[index].apply(this, args) : value;
      while (++index < length) {        result = funcs[index].call(this, result);      }      return result;    };  });}
module.exports = createFlow;