refinement_types/
type_regex.rs

1//! Type-level regular expressions.
2
3pub use regex::Regex;
4
5use crate::static_str::StaticStr;
6
7#[doc(hidden)]
8pub mod import {
9    pub use std::sync::LazyLock;
10}
11
12/// Represents static regular expressions (as returned in [`get`] of [`TypeRegex`]).
13///
14/// [`get`]: TypeRegex::get
15pub type StaticRegex = &'static Regex;
16
17/// Represents type-level regular expressions.
18pub trait TypeRegex {
19    /// Returns the compiled regular expression.
20    fn get() -> StaticRegex;
21}
22
23/// The `invalid regex` literal.
24pub const INVALID: StaticStr = "invalid regex";
25
26/// Lifts strings to type-level regular expressions.
27///
28/// ```
29/// use refinement_types::type_regex;
30///
31/// type_regex!(Integer = "^0|[1-9][0-9]*$");
32/// ```
33///
34/// Is equivalent to:
35///
36/// ```
37/// use std::sync::LazyLock;
38///
39/// use refinement_types::{Regex, StaticRegex, TypeRegex};
40///
41/// #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
42/// struct Integer;
43///
44/// impl TypeRegex for Integer {
45///     fn get() -> StaticRegex {
46///         static REGEX: LazyLock<Regex> = LazyLock::new(|| {
47///             Regex::new("^0|[1-9][0-9]*$").expect("invalid regex")
48///         });
49///
50///         LazyLock::force(&REGEX)
51///     }
52/// }
53/// ```
54///
55#[macro_export]
56macro_rules! type_regex {
57    ($vis: vis $name: ident = $regex: expr $(=> $doc: expr)?) => {
58        $(
59            #[doc = $doc]
60        )?
61        #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
62        $vis struct $name;
63
64        impl $crate::type_regex::TypeRegex for $name {
65            fn get() -> $crate::type_regex::StaticRegex {
66                use $crate::type_regex::import::LazyLock;
67
68                static REGEX: LazyLock<$crate::type_regex::Regex> = LazyLock::new(|| {
69                    $crate::type_regex::Regex::new($regex).expect($crate::type_regex::INVALID)
70                });
71
72                LazyLock::force(&REGEX)
73            }
74        }
75    };
76}
refinement_types/type_regex.rs

refinement_types/
type_regex.rs
