rec 0.6.0

Regular Expression Constructor


Regular Expression Constructor - the recreational version of regular expressions

rec is a Rust library that simplifies the process of writing, reading, and using regular expressions. This library is intended for all users working with regular expressions, no matter their familiarity with regular expression syntax. Below is a summary of the functionality provided by rec:

  • WYSIWYG: [&str] is interpreted exactly as written (i.e. no metacharacters); all metacharacters (as well as other useful patterns) are provided by the [Ch] struct.
  • Simple to understand quantifier and capture group syntaxes.
  • Uses operators to provide easy to understand expressions.
  • [Pattern] expands on [Regex] API to simplify access to data.

This library utilizes the [regex] crate.

Getting Started

Add the following to your Cargo.toml:

rec = "0.6.0"


Use Regex API.

A [Pattern] is a smart pointer to a [Regex], so one can call the same functions.

use rec::{some, Ch, Pattern};

let pattern = Pattern::new("hello" + some(Ch::whitespace()) + (Ch::digit() | "world"));

assert!(pattern.is_match("hello    world"));

Use Pattern to capture a group.

[Pattern] additionally provides helper functions to reduce boilerplate.

use rec::{some, tkn, var, Element, Pattern};
use rec::Ch;

let decimal_number = Pattern::new(tkn!("whole" => some(Ch::digit())) + "." + var(Ch::digit()));

assert_eq!(decimal_number.named_capture_str("23.2", "whole"), Some("23"));


I know regular expression syntax; why should I use rec?

In order for code to be easily maintainable, it should be as simple as possible. Even if the original developer understands their regular expression, it is beneficial for the project as a whole if all contributors are able to easily understand the function of a regular expression.

License: MIT