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Programming-Idioms

  • Scheme
  • Js

Idiom #91 Load JSON file into object

Read from the file data.json and write its content into the object x.
Assume the JSON data is suitable for the type of x. 

const fs = require('fs');
const x = JSON.parse(fs.readFileSync('./data.json'));
const x = require('./data.json');

require() caches when requiring a file for the first time and then uses that cache for future require() calls, so use fs.readFileSync() if the content of the JSON file changes during runtime.
(require '[clojure.java.io :refer [file]])
(require '[jsonista.core :refer [read-value]])
(def x (read-value (file "data.json")))
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const x = JSON.parse(fs.readFileSync('./data.json'));
const x = require('./data.json');
(def x (read-value (file "data.json")))
JObject x = JObject.Parse(File.ReadAllText("data.json"));

JSONValue x = "data.json".readText.parseJSON;

struct User {
    int age;
    string name;

    this(JSONValue user) {
        age  = user["age"];
        name = user["name"];
    }
}

auto user = User(x);
Map x = json.jsonDecode(await new File('data.json').readAsString());
Map x = json.jsonDecode(new File('data.json').readAsStringSync());
defmodule JsonTest do
  def get_json(filename) do
    with {:ok, body} <- File.read(filename),
         {:ok, json} <- Poison.decode(body), do: {:ok, json}
  end
end

x = JsonTest.get_json("data.json")
r, err := os.Open(filename)
if err != nil {
	return err
}
decoder := json.NewDecoder(r)
err = decoder.Decode(&x)
if err != nil {
	return err
}
buffer, err := os.ReadFile("data.json")
if err != nil {
	return err
}
err = json.Unmarshal(buffer, &x)
if err != nil {
	return err
}
file = io.open("data.json")
x = cjson.decode(file:read("a"))
file:close()

$x = json_decode(file_get_contents('data.json'));
my $str = read_file('data.json');
my $x = decode_json($str);
with open("data.json", "r") as input:
    x = json.load(input)
x = JSON.parse(File.read('data.json'))
let x = ::serde_json::from_reader(File::open("data.json")?)?;