You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: backtrack.rs
    path of file: ./repos/regex/regex-cli/args
    
    the code of the file until where you have to start completion: use {
    anyhow::Context,
    lexopt::{Arg, Parser},
    regex_automata::nfa::thompson::{backtrack, NFA},
};

use crate::args::{self, Configurable, Usage};

/// This exposes the configuration knobs for a `BoundedBacktr
    
    fn usage(&self) -> &[Usage] {
        const USAGES: &'static [Usage] = &[Usage::new(
            "--visited-capacity <capacity>",
            "Set the visited capacity for the bounded backtracker.",
            r#"
Set the visited set capacity used to bound backtracking.

The visited capacity represents the amount of heap memory (in bytes) to
allocate toward tracking which parts of the backtracking search have been done
before. The heap memory needed for any particular search is proportional to
'haystack.len() * nfa.states().len()', whichc an be quite large. Therefore, the
bounded backtracker is typically only able to run on shorter haystacks.

For a given regex, increasing the visited capacity means that the maximum
haystack length that can be searched is increased.

The default capacity is a reasonable but empirically chosen size.
"#,
        )];
        USAGES
    }