Macro pkg_version_major

macro_rules! pkg_version_major {
    ($($proc_macro:tt)*) => { ... };
}

Expands to the major version number of the Cargo package, as an integer literal.

The resulting integer literal is unsuffixed, meaning that it does not use a type suffix like 1u32. This means that it can be used to initialize a variable of any integer type, as long as the version number fits. If the number doesn’t fit, the compiler will report an error.