Recap deserializes structures from regex named capture groups extracted from strings.

You may find this crate useful for cases where input is provided as a raw string in a loosely structured format. A common use case for this is when you're dealing with log file data that was not stored in a particular structed format like JSON but rather in a format that can be represented with a pattern.

Recap is provides what envy provides environment variables for named regex capture groups

Examples

Below is an example that derives a FromStr for your type that will parse into the struct using named capture groups

use recap::Recap;
use serde::Deserialize;
use std::error::Error;

#[derive(Debug, Deserialize, PartialEq, Recap)]
#[recap(regex=r#"(?P<foo>\S+)\s(?P<bar>\S+)"#)]
struct Example {
foo: String,
bar: String,
}

fn main() -> Result<(), Box<dyn Error>> {

assert_eq!(
"hello there".parse::<Example>()?,
Example {
foo: "hello".into(),
bar: "there".into()
}
);

Ok(())
}

You can also use recap by using the generic function from_captures in which case you'll be reponsible for bringing your only Regex reference.

💡 For convenience the regex crate's Regex type is re-exported

use recap::{Regex, from_captures};
use serde::Deserialize;
use std::error::Error;

#[derive(Debug, Deserialize, PartialEq)]
struct Example {
foo: String,
bar: String,
}

fn main() -> Result<(), Box<dyn Error>> {
let pattern = Regex::new(
r#"(?P<foo>\S+)\s(?P<bar>\S+)"#
)?;

let example: Example = from_captures(
&pattern, "hello there"
)?;

assert_eq!(
example,
Example {
foo: "hello".into(),
bar: "there".into()
}
);

Ok(())
}