Regexpr

Rust library for regular expressions

lib.rs:

Regular Expressions

This crate provides a [Regex] struct that compiles and tests regular expressions.

Example

use regexpr::Regex;

let regex = Regex::compile(r#"^a(.)c\1.*$"#).unwrap();
assert!(regex.test("abcb"));
assert!(regex.test("abcbde"));
assert!(!regex.test("bcdsd"));
assert!(!regex.test("abcd"));

Rules

[^min_max]: If min or max are not present, it means there's no limit on that size.
Examples:
{,12} matches a rule up to 12
{3,} matches a rule at least 3 times.
{,} is the same as *

[^ranged]: The ranges can be mixed.
Examples:
[a-z123]: Matches any character in the ranges a-z , 1, 2 or 3
[^0-9ab]: Matches a character that IS NOT a number or a or b

[^esc]: Example: "\." Matches a literal dot character.

[^group]: This captured groups can be later referenced

[^capture]: n must be an integer in the range [1,L] where L is the number of capture groups in the expression

Greedy vs. Lazy

"Lazy" versions of * and + exist.
*? and +? work just as * and +, but they stop as soon as possible.

Example

    Regex: .*b
    Input: aaaaaabaaaaab
    Matches: One match "aaaaaabaaaaab"

    Regex: .*?b
    Input: aaaaaabaaaaab
    Matches: Two matches "aaaaaab" and "aaaaab"