Rust regex pattern - unrecognized escape pattern

Question

I do have following string:

\\\"lengthSeconds\\\":\\\"2664\\\"

which I would like to match with this regexp:

Regex::new(\"lengt         


        

Answer 1

By using r#..#, you treat your string as a raw string and hence do not process any escapes. However, since backslashes are special characters in Regex, the Regex expression itself still requires you to escape backslashes. So this

Regex::new(r#"\\"lengthSeconds\\":\\"(\d+)\\""#)

is what you want.

Alternatively, you could write

Regex::new("\\\\\"lengthSeconds\\\\\":\\\\\"(\\d+)\\\\\"").unwrap();

to yield the same result.

See this example on Rust Playground