Macro newstr::use_required

macro_rules! use_required {
    () => { ... };
    (regex) => { ... };
}

This macro expands to the set of use statements required by a consumer of either is_valid_newstring or from_str_newstring macros. This can be valuable over time if the implementationof these macros take on additional dependencies.

The macro takes a single, optional, parameter regex which will also include the necessary dependencies used by the regex_is_valid macro.

Examples

use_required!();

is_valid_newstring!(NotEmpty, |s: &str| !s.is_empty());

use_required!(regex);

regex_is_valid!(r"[0-9]+", is_valid_integer);