Macro ensure

macro_rules! ensure {
    ($cond:expr, $error_kind:expr, $fmt:expr $(, $args:expr)* $(,)?) => { ... };
}

Create a new error with file/line info attached

This macro automatically appends file/line info to the traceback

Arguments

• kind - The kind of the error
• msg - The message of the error
• args - The posisble format arguments

Returns

• Result<(), Error> - The result of the safe call