You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
34 lines
1.0 KiB
Plaintext
34 lines
1.0 KiB
Plaintext
---
|
|
source: tests/output.rs
|
|
expression: "get_stdout(&[item])"
|
|
---
|
|
anyhow Macro anyhow::ensure rusty-man
|
|
|
|
SYNOPSIS
|
|
macro_rules! ensure {
|
|
($cond:expr, $msg:literal $(,)?) => { ... };
|
|
($cond:expr, $err:expr $(,)?) => { ... };
|
|
($cond:expr, $fmt:expr, $($arg:tt)*) => { ... };
|
|
}
|
|
|
|
DESCRIPTION
|
|
Return early with an error if a condition is not satisfied.
|
|
|
|
This macro is equivalent to `if !$cond { return Err(From::from($err)); }`.
|
|
|
|
Analogously to `assert!`, `ensure!` takes a condition and exits the function if the condition
|
|
fails. Unlike `assert!`, `ensure!` returns an `Error` rather than panicking.
|
|
|
|
# Example
|
|
|
|
ensure!(user == 0, "only user 0 is allowed");
|
|
#[derive(Error, Debug)]
|
|
enum ScienceError {
|
|
#[error("recursion limit exceeded")]
|
|
RecursionLimitExceeded,
|
|
...
|
|
}
|
|
ensure!(depth <= MAX_DEPTH, ScienceError::RecursionLimitExceeded);
|
|
|
|
|