About guard let syntax

Question

let e: String? = "novel"
guard let f = e
else { return }
print(f)

i got error like below if I code like above

Playground execution failed:

error: dotinstall.playground:175:12: error: return invalid outside of a func
else { return }

I wanna use "guard let syntax " without "func()"

I tried it in some ways, but its wasn't worked well.I know almost the "guard let syntax " usually used with "func()". But if I try it with "if let syntax " it was worked without error like below

let S: String? = "jjjj"
if let Thailand = S {
    print(Thailand)}

please show me how can I code with "guard let" without "func()"

You can use `fatalError()`, use anything that doesn't continue, use something like `break`, `return`, `continue`, `fatalError()`, or anything that returns `Never`, etc... — user9335240, Feb 21 '18 at 14:23
This error caused by ```return``` statement. This error is not related ```guard let``` — Emre Ozdil, Feb 21 '18 at 14:29
See [`guard vs if-let`](https://stackoverflow.com/a/39263210/5175709). Scroll down to *Guard requires scope exiting* — mfaani, Feb 21 '18 at 14:57

score 4 · Accepted Answer · answered Feb 21 '18 at 14:24

4

Try this in playground:

guard let f = e else { fatalError("s is nil") }

Hope it helps!

answered Feb 21 '18 at 14:24

Agent Smith

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Thank you for your answer. why it isn't worked if I put return in ()? – revoiot Feb 21 '18 at 14:26
Because it is not a function. Return must be in a function, not in a top level code – user9335240 Feb 21 '18 at 14:27
@revoiot because you return from a function/method scope. Since there are none of them, Just a statement, You cannot return from the scope. – Agent Smith Feb 21 '18 at 14:28
thank you very much!!! I solved the problem !!! – revoiot Mar 21 '18 at 13:27

About guard let syntax

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