[−][src]Crate rec

Regular Expression Constructor - making regular expressions fun

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 ChCls enum.
Simple to understand quantifier syntax and capture name syntax.
Uses operators to provide easy to understand expressions.
Pattern returns exactly what is requested to reduce boilerplate.

This library utilizes the regex crate.

Getting Started

Add the following to your Cargo.toml:

[dependencies]
rec = "0.4"

Examples

Create a Regex

If you prefer API of regex, you can use a Rec to construct a Regex.

use rec::{some};
use rec::ChCls::{Digit, Whitespace};

let a_rec = "hello" + some(Whitespace) + (Digit | "world");
let regex = a_rec.build();

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

Use Pattern to tokenize

Instead of using Regex, you can use Pattern to handle basic matching needs.

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

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

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

FAQ

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.

Macros

tkn	Creates a capture group with a given name.

Structs

Location	Represents where in the target that a match was found.
Locations	Iterates through a target, returning the `Location` of each match.
Pattern	Represents a regular expression to be matched against a target.
Rec	Constructs a regular expression.
Tokens	Stores the possible matches of a `Pattern` against a target.
TokensIter	Iterates through a given target returning each `Tokens` found.

btwn	Returns a `Rec` representing the given `Element` repeated between 2 numbers.
exact	Returns a `Rec` representing the given `Element` repeated a given number of times.
lazy_btwn	Returns a `Rec` representing the given `Element` lazily repeated a range of given times.
lazy_min	Returns a `Rec` representing the given `Element` lazily repeated at least a given number of times.
lazy_opt	Returns a `Rec` representing the given `Element` lazily repeated 0 or 1 times.
lazy_some	Returns a `Rec` representing the given `Element` lazily repeated 1 or more times.
lazy_var	Returns a `Rec` representing the given `Element` lazily repeated 0 or more of times.
min	Returns a `Rec` representing the given `Element` repeated at least a given number of times.
opt	Returns a `Rec` representing the given `Element` greedily repeated 0 or 1 times.
some	Returns a `Rec` representing the given `Element` greedily repeated 1 or more times.
var	Returns a `Rec` representing the given `Element` greedily repeated 0 or more times.