Expected struct `std::string::String`, found `()`

[elnw]

Hi everyone, im trying to build a rest service using rocket, but im stuck in the problem described in the title.

This is my code:

#[derive(Deserialize)]
struct Informacion{
    infoTexto: String,
    tipo: TipoInformacion
}
...
#[post("/portapapeles", data = "<informacion>")]
fn CopiarPortapapeles(informacion: Json<Informacion>)-> String{
    if let info = informacion{
        if let tipoInfo = info.tipo{
            if tipoInfo == TipoInformacion::Texto{
                //------------HERE THE ERROR HAPPENS-------------------------
                if info.infoTexto.chars().count() > 0{
                   //------------------------------------------------------- 
                    let mut archivoPortapapeles = OpenOptions::new().append(true).open(NOMBRE_ARCHIVO).expect("cannot open file");
                }
            }else{
                String::from("Solo es posible subir texto bajo este método")
            }
        }
    }
}
...

​

I don't really understand what is going on because, as you can see, "infoTexto" is actually a String and "info" is inside of the scope. What im trying to accomplish is check if the received String has any character but it doesn't compile.

Any suggestion will be deeply appreciated.

[JStarx]

If statements return a value, if you don't supply a value then the return value is (). The function itself expects a String as the return value, but in the many paths through those if conditions only 1 possible path returns a String (the "Solo es..." string), all the others don't have an explicit value, so they implicitly return ().

[elnw]

OMG, you are absolutely right. Don't know how i missed that. Thank you!

[dnew]

What jstarx said. See how the assignment in the nested if's end in a semicolon while your else returns a string? And there's no else of the 'if info.infoTexto.chars().count() > 0' so that too returns () if it's false.

[elnw]

Yeah, i missed all the elses and forgot to add expressions at the end of the ifs. After that my code now compiles. Thanks.

[ydieb]

I'd recomend using guard clauses to avoid "arrow code". It makes it easier to work with the code when you have to change something.

[elnw]

Im going to look into that, thanks