RepoDecode.swift

import Foundation

struct Repo: Decodable {
    let name: String
    let private: Bool
    let language: String
}

let json = """
[
    {
        "name": "SignUp",
        "private": false,
        "language": "Swift"
    },
    {
        "name": "tomate",
        "private": false,
        "language": "Swift"
    },
    {
        "name": "springmemo",
        "private": false,
        "language": "Python"
    }
]
""".data(using: .utf8)!

let repos = try JSONDecoder().decode([Repo].self, from: json)
repos.forEach { print($0) }