Handling Typed Errors in JWT Verification with Functional Programming in TypeScript

Hello folk,
I try to find an elegant solution to type Error from popular librairy. For example here : jsonwebtoken (jwt).
.verify of jwt could throw a typed VerifyError

The question here is how can I use this typed error when I'm using jwt with Effect.try ?

const verifyTokenEffect = (secret: string) => (token: string): T.Effect<string | JwtPayload, Error, never> =>
  T.try(() => jwt.verify(token, secret)).pipe(T.mapError(e => new Error(e.message)))

const verifyTokenEffect = (secret: string) => (token: string): T.Effect<string | JwtPayload, Error, never> =>
  T.try(() => jwt.verify(token, secret)).pipe(T.mapError(e => new Error(e.message)))

Here with a catch clause but similar to try ... catch

const verifyTokenEffect = (secret: string) => (token: string): T.Effect<string | JwtPayload, VerifyErrors, never> =>
  T.try({
    try: () => jwt.verify(token, secret),
    catch: error => error as VerifyErrors
  })

const verifyTokenEffect = (secret: string) => (token: string): T.Effect<string | JwtPayload, VerifyErrors, never> =>
  T.try({
    try: () => jwt.verify(token, secret),
    catch: error => error as VerifyErrors
  })

`

In FP, I'm using something like that, the error is "forced" cast to the typed I gave

const verifyTokenEither = (secret: string) => (token: string): Either<string | JwtPayload, VerifyErrors> =>
  myFpMonad.try<string | JwtPayload, VerifyErrors>(() => jwt.verify(token, secret))

const verifyTokenEither = (secret: string) => (token: string): Either<string | JwtPayload, VerifyErrors> =>
  myFpMonad.try<string | JwtPayload, VerifyErrors>(() => jwt.verify(token, secret))

Maybe, I'm doing wrong.

If not ,my point of vue : If we're knowing what kind of errors are thrown from some external / legacy code (jsonwebtoken, zod, Axios ...), we could have the possibility to forced the cast on the Effect.try call.

What do you thing?

Handling Typed Errors in JWT Verification with Functional Programming in TypeScript

const verifyTokenEffect = (secret: string) => (token: string): T.Effect<string | JwtPayload, Error, never> =>
  T.try(() => jwt.verify(token, secret)).pipe(T.mapError(e => new Error(e.message)))

const verifyTokenEffect = (secret: string) => (token: string): T.Effect<string | JwtPayload, Error, never> =>
  T.try(() => jwt.verify(token, secret)).pipe(T.mapError(e => new Error(e.message)))

Here with a catch clause but similar to try ... catch

const verifyTokenEffect = (secret: string) => (token: string): T.Effect<string | JwtPayload, VerifyErrors, never> =>
  T.try({
    try: () => jwt.verify(token, secret),
    catch: error => error as VerifyErrors
  })

const verifyTokenEffect = (secret: string) => (token: string): T.Effect<string | JwtPayload, VerifyErrors, never> =>
  T.try({
    try: () => jwt.verify(token, secret),
    catch: error => error as VerifyErrors
  })

`

In FP, I'm using something like that, the error is "forced" cast to the typed I gave

const verifyTokenEither = (secret: string) => (token: string): Either<string | JwtPayload, VerifyErrors> =>
  myFpMonad.try<string | JwtPayload, VerifyErrors>(() => jwt.verify(token, secret))

const verifyTokenEither = (secret: string) => (token: string): Either<string | JwtPayload, VerifyErrors> =>
  myFpMonad.try<string | JwtPayload, VerifyErrors>(() => jwt.verify(token, secret))

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