75 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			75 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| var SetCache = require('./_SetCache'),
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|     arrayIncludes = require('./_arrayIncludes'),
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|     arrayIncludesWith = require('./_arrayIncludesWith'),
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|     arrayMap = require('./_arrayMap'),
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|     baseUnary = require('./_baseUnary'),
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|     cacheHas = require('./_cacheHas');
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| 
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| /* Built-in method references for those with the same name as other `lodash` methods. */
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| var nativeMin = Math.min;
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| 
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| /**
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|  * The base implementation of methods like `_.intersection`, without support
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|  * for iteratee shorthands, that accepts an array of arrays to inspect.
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|  *
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|  * @private
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|  * @param {Array} arrays The arrays to inspect.
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|  * @param {Function} [iteratee] The iteratee invoked per element.
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|  * @param {Function} [comparator] The comparator invoked per element.
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|  * @returns {Array} Returns the new array of shared values.
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|  */
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| function baseIntersection(arrays, iteratee, comparator) {
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|   var includes = comparator ? arrayIncludesWith : arrayIncludes,
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|       length = arrays[0].length,
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|       othLength = arrays.length,
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|       othIndex = othLength,
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|       caches = Array(othLength),
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|       maxLength = Infinity,
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|       result = [];
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| 
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|   while (othIndex--) {
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|     var array = arrays[othIndex];
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|     if (othIndex && iteratee) {
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|       array = arrayMap(array, baseUnary(iteratee));
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|     }
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|     maxLength = nativeMin(array.length, maxLength);
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|     caches[othIndex] = !comparator && (iteratee || (length >= 120 && array.length >= 120))
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|       ? new SetCache(othIndex && array)
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|       : undefined;
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|   }
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|   array = arrays[0];
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| 
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|   var index = -1,
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|       seen = caches[0];
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| 
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|   outer:
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|   while (++index < length && result.length < maxLength) {
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|     var value = array[index],
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|         computed = iteratee ? iteratee(value) : value;
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| 
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|     value = (comparator || value !== 0) ? value : 0;
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|     if (!(seen
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|           ? cacheHas(seen, computed)
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|           : includes(result, computed, comparator)
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|         )) {
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|       othIndex = othLength;
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|       while (--othIndex) {
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|         var cache = caches[othIndex];
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|         if (!(cache
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|               ? cacheHas(cache, computed)
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|               : includes(arrays[othIndex], computed, comparator))
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|             ) {
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|           continue outer;
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|         }
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|       }
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|       if (seen) {
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|         seen.push(computed);
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|       }
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|       result.push(value);
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|     }
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|   }
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|   return result;
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| }
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| 
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| module.exports = baseIntersection;
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