private! protected! const! JSON parse directives

💡 Ideas
1 
private! 
protected! 
const! JSON parse directives

myJSON = { 
    const! Apple:"Macintosh", // read-only!
    protected! Macintosh:"Delicious", // read-only! nocopy!
    private! Delicious:"Always", // noread! nocopy!
    private! { DeliciousAlso:"Always", ALocalOnlyPassword:"SavedLocallyInAFileWhichWillNotBeLoadedAtRuntimeOrTransferedOverTheNetwork"... },
}

myJSON.Apple // Macintosh
myJSON.Macintosh // Delicious
myJSON.Delicious // Error Access of property for read or assign is restricted!

let myVarA = myJSON.Apple // Macintosh
let myVarB = myJSON.Macintosh // null
let myVarC = myJSON.Delicious // Error Access of property for read or assign is restricted!

myVarA = myJSON.Apple = 100 // Error Cannot assign const to a value!
myVarB = myJSON.Macintosh = 100 // null
myVarC = myJSON.Delicious = 100 // Error Access of property for read or assign is restricted!

console.log( myJSON.Apple ) // Macintosh
console.log( myJSON.Macintosh ) // Delicious
console.log( myJSON.Delicious ) // Always
2

If you can't read it, you can't print it.

3

just fyi in real-world-problems, if i want a json-object to be immutable, an effective poorman's solution is to store it in JSON.stringify'd form:

let readOnlyConfig = JSON.stringify({
    Apple: "Macintosh", // read-only!
    Macintosh: "Delicious" // read-only! nocopy!
});

console.log( JSON.parse(readOnlyConfig).Apple     ); // Macintosh
console.log( JSON.parse(readOnlyConfig).Macintosh ); // Delicious

// plus the data is easier to message-pass (which is always a plus in javascript)
postMessage(readOnlyConfig);
4

@kaizhu256 There is Object.freeze for that. It's more performant, reliable and robust solution.

3 Likes
5

What's the use case (beyond a possible #key: value private property for objects)?