Rust: concatenating two expr.to_string() values

Question

How do I resolve this? The execution is a return from process::Command .output().

let mut gradinglog = std::str::from_utf8(&execution.stdout).unwrap().to_string() + 
std::str::from_utf8(&execution.stderr).unwrap().to_string();

Compilation error log:

error[E0308]: mismatched types
   --> src/main.rs:270:87
    |
270 | ...rap().to_string() + std::str::from_utf8(&execution.stderr).unwrap().to_string();
    |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                                 |
    |                                 expected `&str`, found struct `std::string::String`
    |                                 help: consider borrowing here: `&std::str::from_utf8(&execution.stderr).unwrap().to_string()`

Does the *"help:"* annotation in the error message not solve your problem? An alternative solution is to drop the last `.to_string()` since `str::from_utf8().unwrap()` already returns a `&str`. — kmdreko, Apr 18 '21 at 21:43

score 0 · Answer 1 · answered Apr 18 '21 at 21:37

0

Ah this is strange but... I managed to concatenate using a simple format!("{}{}", string1, string2);

answered Apr 18 '21 at 21:37

ArekBulski

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Rust: concatenating two expr.to_string() values

1 Answers1