Function Class 

pub const fn Class(value: &'static str) -> Class

Class code constant constructor

Can be used to define constant values for Class from string literals.

Use Class::from_str() for non-literals.

Panics

Panics if the passed string is not a valid class code.

Examples

const MY_ERROR_CLASS: Class = Class("XR");

let sqlstate = some_db_query_function(..);

match sqlstate.class() {
  MY_ERROR_CLASS => println!("got an error in my expected class"),
  _ => panic!("unexpected condition")
}

An invalid class code in a constant context will cause a compile time panic:

const MY_ERROR_CLASS: Class = Class("!R"); // error: evaluation of constant value failed

but an invalid class code in a non-constant context may only panic at runtime:

let some_class = Class("!R"); // panics