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< a class = "header" href = "#simple-string-errors" id = "simple-string-errors" > < h1 > Simple String Errors< / h1 > < / a >
< p > The most simplest of doing error handling in rust is by returning < code > String< / code > as a < code > Box< Error> < / code > .< / p >
< p > As you can see by running the example, this only prints out the last < code > Error< / code > .< / p >
< p > If the rust < code > main< / code > function returns an Err(), this Err() will be displayed with < code > std::fmt::Debug< / code > .< / p >
< pre > < pre class = "playpen" > < code class = "language-rust" > use std::error::Error;
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use std::result::Result;
fn do_some_io() -> Result< (), Box< Error> > {
Err(" do_some_io error" )?;
Ok(())
}
fn func2() -> Result< (), Box< Error> > {
if let Err(_) = do_some_io() {
Err(" func2 error" )?;
}
Ok(())
}
fn func1() -> Result< (), Box< Error> > {
if let Err(_) = func2() {
Err(" func1 error" )?;
}
Ok(())
}
fn main() -> Result< (), Box< Error> > {
func1()
}
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