Implement JSON.parse (Medium)
Good afternoon! Here's our prompt for today.
In JavaScript by default, there is a method that can parse a given JSON string, and it can be invoked by calling JSON.parse(). The way this method works is constructing the JavaScript value or object described by the string.
Can you implement your own version of this method, called parseJSON, accepting one parameter (the JSON string), keeping in mind all the value types and restrictions in the JSON format?
1function parseJSON(input) {
2 // fill in this method
3}Your task is to create a function called parseJSON that takes a string as input and returns the corresponding JavaScript object. The function should be able to handle JSON-like strings, which can be:
- Primitive types:
null,true,false - Strings wrapped in quotes:
"string" - Arrays:
[1, "a", null] - Objects:
{"key": "value", "anotherKey": 42}
Your parser should return the corresponding JavaScript types for these string inputs. For example, if the input string is "null", your function should return null.
xxxxxxxxxxfunction parseJSON(input) { // if the input is empty or starts with an invalid character, throw an error if (input === "" || input[0] === "'") { throw Error(); } // check if the input is null, an empty object, empty array, or a boolean and return the value from the input if (input === "null") { return null; } if (input === "{}") { return {}; } if (input === "[]") { return []; } if (input === "true") { return true; } if (input === "false") { return false; } //if the input starts with a quote, return the value from inside the quotes if (input[0] === '"') { return input.slice(1, -1);