8 lines
		
	
	
		
			203 B
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
			
		
		
	
	
			8 lines
		
	
	
		
			203 B
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
| /**
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|  * Groups array items into a Map, given a function to produce grouping key.
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|  */
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| export declare function groupBy<K, T>(
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|   list: ReadonlyArray<T>,
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|   keyFn: (item: T) => K,
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| ): Map<K, ReadonlyArray<T>>;
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