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JavaScript: Difference between revisions
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===Objects=== | ===Objects=== | ||
Objects are maps in JavaScript. They are typically implemented as hashmaps by the JS engine.<br> | Objects are maps in JavaScript. They are typically implemented as hashmaps by the JS engine.<br> | ||
Note that you can only use numbers and strings as keys. | Note that you can only use numbers and strings as keys.<br> | ||
Learn more about the implementation at [https://v8.dev/blog/hash-code https://v8.dev/blog/hash-code]<br> | |||
<syntaxhighlight lang="javascript"> | <syntaxhighlight lang="javascript"> | ||
let my_map = {}; | let my_map = {}; | ||
my_map["my_key"] = "my_value"; | // or my_map["my_key"] | ||
my_map.my_key = "my_value"; | |||
"my_key" in my_map; | "my_key" in my_map; | ||