Brute forcing errors with loops angering the borrow checker

[narrow blade]

I'm trying to brute force a web request to work with loops, however when I try to nest it with another brute force it gives me a borrow checker error says that it get's moved (val.text() is fn text(self), so it takes ownership). I get why it takes ownership, I just don't get why it matters. I'm not using val after I move it, so I'm confused.

Here is a simplified version of what I'm trying to do (also note that I'm writing this on the fly, so it may not be 100% semantically correct)

        fn foo() -> String {
          loop {
            match server.send_request() {
                Ok(val) => loop {
                    match val.text() {
                        Ok(val) => return Ok(val),
                        Err(err) => println!("Warning: failed to get query text; Error: {}", err)
                    }
                },
                Err(err) => println!("Warning: failed to query data; Error: {}", err)
            }
        }

[twin scarab]

If you can provide some actual errors, that would be helpful

-errors

[terse epoch]

If you're getting large or confusing errors please post the full error message from cargo check in a code block instead of the errors in your IDE so that we can understand your problem better:

```rust
// error from cargo check here
```

[narrow blade]

error[E0382]: use of moved value: `val`
   --> src/main.rs:32:27
    |
31  |                 Ok(val) => loop {
    |                    ---     ---- inside of this loop
    |                    |
    |                    move occurs because `val` has type `reqwest::blocking::Response`, which does not implement the `Copy` trait
32  |                     match val.text() {
    |                           ^^^ ------ `val` moved due to this method call, in previous iteration of loop
    |
note: `reqwest::blocking::Response::text` takes ownership of the receiver `self`, which moves `val`
   --> /home/usr/.cargo/registry/src/index.crates.io-6f17d22bba15001f/reqwest-0.11.23/src/blocking/response.rs:282:17
    |
282 |     pub fn text(self) -> crate::Result<String> {
    |                 ^^^^

For more information about this error, try `rustc --explain E0382`.
error: could not compile `webscraper` (bin "webscraper") due to previous error```

[twin scarab]

val moved due to this method call, in previous iteration of loop

and there you have it

though I'm not sure why you have the inner loop there

[narrow blade]

I need to keep running val.text() until it returns Ok()

[twin scarab]

you can't call val.text() twice, since it consumes val as you noted yourself

the outer loop, which repeatedly sends requests, makes sense to me

the inner doesn't (and causes the error)

[narrow blade]

oh it's because val.text() gets dropped. I was thinking that it moves it into the loop context, and only gets dropped after the loop finishes

I didn't relize it was dropped after one iteration

[twin scarab]

dropping has nothing to do with it

[narrow blade]

moving?

[twin scarab]

yes

your code basically does

match val.text() { ... }
match val.text() { ... }
match val.text() { ... }
...

after the first call to text, val has been moved into that function and you no longer own it

besides that, val.text() is most likely pure, and will not give you different results by calling it multiple times (ignore the fact that this is impossible in the first place)