regex_quote_fixer

The Regex Quote Fixer rewrites grep regexpressions for the use in the regex crate.

This crate allows to translate between regexpressions of different regexpression implementations by deciding when to add or remove the metachar '\' from the regexpression string.

Example:

use regex_quote_fixer::RegexQuoteFixer;
let rqf = RegexQuoteFixer::for_grep();

// as used with grep
let needle = r#"https\?://\([[:alnum:].]*\.\)\?example\.com/"#;

let needle_fixed = rqf.fix( needle);

assert_eq!( needle_fixed, r#"https?://([[:alnum:].]*\.)?example\.com/"#);

use regex::Regex;

let regex = Regex::new( &needle_fixed).unwrap();

assert!( regex.is_match( r#"https://www.example.com/"#));
assert!( regex.is_match( r#"http://www.example.com/"#));
assert!( regex.is_match( r#"http://example.com/"#));

// and it is also possible to convert regex compatible regexpressions
// to grep regexpressions :

let needle2 = rqf.fix( &needle_fixed);

assert_eq!( needle, needle2);

Another Example:

use regex_quote_fixer::RegexQuoteFixer;
let rqf = RegexQuoteFixer::for_grep();

// as used with grep
let needle = r#"^a\+[]\?]b\+$"#;

let needle_fixed = rqf.fix( needle);

assert_eq!( needle_fixed, r#"^a+[]\\?]b+$"#);

use regex::Regex;

let regex = Regex::new( &needle_fixed).unwrap();

assert!( regex.is_match( r#"a]b"#));
assert!( regex.is_match( r#"aa]bb"#));
assert!( regex.is_match( r#"a?b"#));
assert!( regex.is_match( r#"a\b"#));

// and it is also possible to convert this regex compatible regexpression
// to a grep compatible regexpressions :

let needle2 = rqf.fix( &needle_fixed);

assert_eq!( needle, needle2);

It is also possible to operate with free defined quote chars:

use regex_quote_fixer::RegexQuoteFixer;
use regex_quote_fixer::CharacterClass;

let rqf = RegexQuoteFixer {
 lambda: Box::new(|x| x == 'b'),
 quote_char: 'c',
 cc: CharacterClass::Ignore,
};
let s1 = "abcccbd";
let s2 = rqf.fix( s1);
assert_eq!( s2, "acbccbd");
let s3 = rqf.fix( &s2);
assert_eq!( s1, s3);