macro_rules! nested_try {
($expr:expr) => { ... };
}Expand description
Helper to perform the try operation over an inner value of a
Result<Result<T, E>, U>, this will check an error of type Result<T, E>
and return it as Ok(Err(E)) if it is.
This is useful because functions in Rune can return different kinds of
errors. One is a critical error for the virtual machine, most typically
VmErro. And another is a logical error that should be returned and handled
by the program.