I rewrote my code to what I think I was trying to accomplish. I cannot wrap my head around using object literals as an alternative to if/else or switch. How would you convert the if/else condition to an Object Literal below?
let bobRes = "A123";
//stored password in database
let sPass = "A1234";
let qState = "q1";
function responseHandler(bobResValue, sPassValue, qStateValue) {
if (sPass === "" && qStateValue === "q1") {
return "Create a new password using five digits.";
} else if (bobResValue.length !== 5 && qStateValue === "q1") {
return "Password is too short!";
} else if (bobResValue !== sPassValue) {
return "Wrong Password";
} else if (bobResValue === sPass) {
return "Correct Password";
} else {
return "You must enter a password to continue?";
}
}
let finalResponse = responseHandler(bobRes, sPass, qState);
console.log(finalResponse)
My attempt to convert to object literal! But I'm stuck on the logic...
let bobRes = "A123";
//stored password in database
let sPass = "A1234";
function responseHandler(bobResValue) {
let respObj = {
"None": "You must enter a password."
}
let respObj2 = {
passWordLength: (bobResValue) => bobResValue.length != 5,
}
let respObj3 = {
passWordLength: (bobResValue) => bobResValue === 5,
}
respObj[bobResValue] ?? respObj2[passWordLength]?? "You must enter a password to continue!";
}
let finalResponse = responseHandler(bobRes, sPass, qState);
console.log(finalResponse)
Don't give up! These kinds of refactors will teach you to identify problems with how you are thinking about the program and permanently unlock new techniques.
This is a practical use case for the Either monad. Don't let unfamiliar terms scare you. Here we demonstrate the technique in a lo-fi way as ok and err. If you have any questions, just ask -
const ok = value => ({
chain: f => f(value),
get: (ifOk, _) => ifOk(value)
})
const err = value => ({
chain: _ => err(value),
get: (_, ifErr) => ifErr(value)
})
const isEmpty = s => (s === "")
? err("create a new password using five digits")
: ok(s)
const isTooShort = s => (s.length != 5 || Number.isNaN(Number.parseInt(s)))
? err("password is not five digits")
: ok(s)
const isMatch = match => s => (s !== match)
? err("wrong password")
: ok(s)
function validate(pass, match) {
return isEmpty(pass)
.chain(isTooShort)
.chain(isMatch(match))
.get(console.log, console.error)
}
validate("", "foo")
validate("123", "123")
validate("12345", "9876")
validate("12345", "12345")Replace console.log with the identity function, v => v, to have validate return the valid password instead of logging it to the console.
Optionally replace console.error with msg => { throw Error(msg) } to have validate throw an error that corresponds to the specific failure.