29 lines
541 B
Markdown
29 lines
541 B
Markdown
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---
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title: Map
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---
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## Map
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A map of `[key, value]` entries, where keys and values can be any value (both objects and primitive values).
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## Syntax
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```javascript
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new Map([iterable])
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```
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## Parameters
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**iterable** An Array or other iterable object whose elements are key-value pairs.
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## Example
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```javascript
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// basic usage
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const myMap = new Map();
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myMap.set('foo',1);
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myMap.set('bar',2);
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myMap.set('baz',3);
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myMap.get('foo'); // returns 1
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myMap.get('baz'); // returns 3
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myMap.get('hihi'); // return undefined
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myMap.size(); // 3
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```
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