| # `dlv(obj, keypath)` [](https://npmjs.com/package/dlv) [](https://travis-ci.org/developit/dlv) |
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| > Safely get a dot-notated path within a nested object, with ability to return a default if the full key path does not exist or the value is undefined |
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| ### Why? |
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| Smallest possible implementation: only **130 bytes.** |
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| You could write this yourself, but then you'd have to write [tests]. |
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| Supports ES Modules, CommonJS and globals. |
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| ### Installation |
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| `npm install --save dlv` |
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| ### Usage |
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| `delve(object, keypath, [default])` |
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| ```js |
| import delve from 'dlv'; |
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| let obj = { |
| a: { |
| b: { |
| c: 1, |
| d: undefined, |
| e: null |
| } |
| } |
| }; |
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| //use string dot notation for keys |
| delve(obj, 'a.b.c') === 1; |
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| //or use an array key |
| delve(obj, ['a', 'b', 'c']) === 1; |
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| delve(obj, 'a.b') === obj.a.b; |
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| //returns undefined if the full key path does not exist and no default is specified |
| delve(obj, 'a.b.f') === undefined; |
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| //optional third parameter for default if the full key in path is missing |
| delve(obj, 'a.b.f', 'foo') === 'foo'; |
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| //or if the key exists but the value is undefined |
| delve(obj, 'a.b.d', 'foo') === 'foo'; |
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| //Non-truthy defined values are still returned if they exist at the full keypath |
| delve(obj, 'a.b.e', 'foo') === null; |
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| //undefined obj or key returns undefined, unless a default is supplied |
| delve(undefined, 'a.b.c') === undefined; |
| delve(undefined, 'a.b.c', 'foo') === 'foo'; |
| delve(obj, undefined, 'foo') === 'foo'; |
| ``` |
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| ### Setter Counterparts |
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| - [dset](https://github.com/lukeed/dset) by [@lukeed](https://github.com/lukeed) is the spiritual "set" counterpart of `dlv` and very fast. |
| - [bury](https://github.com/kalmbach/bury) by [@kalmbach](https://github.com/kalmbach) does the opposite of `dlv` and is implemented in a very similar manner. |
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| ### License |
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| [MIT](https://oss.ninja/mit/developit/) |
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| [preact]: https://github.com/developit/preact |
| [tests]: https://github.com/developit/dlv/blob/master/test.js |
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