mirror of https://github.com/webpack/webpack.git
				
				
				
			
		
			
				
	
	
		
			23 lines
		
	
	
		
			472 B
		
	
	
	
		
			JavaScript
		
	
	
	
			
		
		
	
	
			23 lines
		
	
	
		
			472 B
		
	
	
	
		
			JavaScript
		
	
	
	
| /*
 | |
| 	MIT License http://www.opensource.org/licenses/mit-license.php
 | |
| 	Author Tobias Koppers @sokra
 | |
| */
 | |
| 
 | |
| "use strict";
 | |
| 
 | |
| /**
 | |
|  * @template K
 | |
|  * @template V
 | |
|  * @param {Map<K, V>} map a map
 | |
|  * @param {K} key the key
 | |
|  * @param {function(): V} computer compute value
 | |
|  * @returns {V} value
 | |
|  */
 | |
| exports.provide = (map, key, computer) => {
 | |
| 	const value = map.get(key);
 | |
| 	if (value !== undefined) return value;
 | |
| 	const newValue = computer();
 | |
| 	map.set(key, newValue);
 | |
| 	return newValue;
 | |
| };
 |