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# json 🐑
Work with JSON in Gleam!
Under the hood library uses [Thoas](https://github.com/lpil/thoas/), the fastest
and most memory efficient pure Erlang JSON encoder/decoder.
## Installation
Add this package to your Gleam project.
```shell
gleam add gleam_json
```
### Encoding
```rust
import myapp.{Cat}
import gleam/list
import gleam/json.{object, string, list, int, null}
pub fn cat_to_json(cat: Cat) -> String {
object([
#("name", string(cat.name)),
#("lives", int(9),
#("flaws", null()),
#("nicknames", array(["Kitty", "Sweetie"], of: string)),
])
|> json.to_string
}
```
### Decoding
JSON is decoded into a `Dynamic` value which can be decoded using the
`gleam/dynamic` module from the Gleam standard library.
```rust
import myapp.{Cat}
import gleam/json
import gleam/dynamic
import gleam/result
pub fn cat_from_json(json: String) -> Result<Cat, MyError> {
try data =
json.decode(encoded)
|> result.map_error(InvalidJson)
let data = dynamic.from(data)
try cat = {
try name = dynamic.field(data, "name")
try name = dynamic.string(name)
Ok(Cat(name))
}
|> result.map_error(InvalidFormat)
Ok(cat)
}
pub type MyError {
InvalidJson(json.DecodeError)
InvalidFormat(dynamic.DecodeError)
}
```
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