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var composeArgs = require('./_composeArgs'),    composeArgsRight = require('./_composeArgsRight'),    replaceHolders = require('./_replaceHolders');
/** Used as the internal argument placeholder. */var PLACEHOLDER = '__lodash_placeholder__';
/** Used to compose bitmasks for function metadata. */var WRAP_BIND_FLAG = 1,    WRAP_BIND_KEY_FLAG = 2,    WRAP_CURRY_BOUND_FLAG = 4,    WRAP_CURRY_FLAG = 8,    WRAP_ARY_FLAG = 128,    WRAP_REARG_FLAG = 256;
/* Built-in method references for those with the same name as other `lodash` methods. */var nativeMin = Math.min;
/** * Merges the function metadata of `source` into `data`. * * Merging metadata reduces the number of wrappers used to invoke a function. * This is possible because methods like `_.bind`, `_.curry`, and `_.partial` * may be applied regardless of execution order. Methods like `_.ary` and * `_.rearg` modify function arguments, making the order in which they are * executed important, preventing the merging of metadata. However, we make * an exception for a safe combined case where curried functions have `_.ary` * and or `_.rearg` applied. * * @private * @param {Array} data The destination metadata. * @param {Array} source The source metadata. * @returns {Array} Returns `data`. */function mergeData(data, source) {  var bitmask = data[1],      srcBitmask = source[1],      newBitmask = bitmask | srcBitmask,      isCommon = newBitmask < (WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG | WRAP_ARY_FLAG);
  var isCombo =    ((srcBitmask == WRAP_ARY_FLAG) && (bitmask == WRAP_CURRY_FLAG)) ||    ((srcBitmask == WRAP_ARY_FLAG) && (bitmask == WRAP_REARG_FLAG) && (data[7].length <= source[8])) ||    ((srcBitmask == (WRAP_ARY_FLAG | WRAP_REARG_FLAG)) && (source[7].length <= source[8]) && (bitmask == WRAP_CURRY_FLAG));
  // Exit early if metadata can't be merged.  if (!(isCommon || isCombo)) {    return data;  }  // Use source `thisArg` if available.  if (srcBitmask & WRAP_BIND_FLAG) {    data[2] = source[2];    // Set when currying a bound function.    newBitmask |= bitmask & WRAP_BIND_FLAG ? 0 : WRAP_CURRY_BOUND_FLAG;  }  // Compose partial arguments.  var value = source[3];  if (value) {    var partials = data[3];    data[3] = partials ? composeArgs(partials, value, source[4]) : value;    data[4] = partials ? replaceHolders(data[3], PLACEHOLDER) : source[4];  }  // Compose partial right arguments.  value = source[5];  if (value) {    partials = data[5];    data[5] = partials ? composeArgsRight(partials, value, source[6]) : value;    data[6] = partials ? replaceHolders(data[5], PLACEHOLDER) : source[6];  }  // Use source `argPos` if available.  value = source[7];  if (value) {    data[7] = value;  }  // Use source `ary` if it's smaller.  if (srcBitmask & WRAP_ARY_FLAG) {    data[8] = data[8] == null ? source[8] : nativeMin(data[8], source[8]);  }  // Use source `arity` if one is not provided.  if (data[9] == null) {    data[9] = source[9];  }  // Use source `func` and merge bitmasks.  data[0] = source[0];  data[1] = newBitmask;
  return data;}
module.exports = mergeData;