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: statement.rs
    path of file: ./repos/libsql/libsql/src/local
    
    the code of the file until where you have to start completion: use crate::local::rows::{MappedRows, Row};
use crate::local::{Connection, Rows};
use crate::params::Params;
use crate::{errors, Column, Error, Result, ValueRef};

use std::cell::RefCell;
use std::ffi::c_int;
use std::sync::Arc;

/// A prepared 
    
    pub fn column_index(&self, name: &str) -> Result<usize> {
        let bytes = name.as_bytes();
        let n = self.column_count() as i32;
        for i in 0..n {
            // Note: `column_name` is only fallible if `i` is out of bounds,
            // which we've already checked.
            let col_name = self
                .inner
                .column_name(i)
                .ok_or_else(|| Error::InvalidColumnName(name.to_string()))?;
            if bytes.eq_ignore_ascii_case(col_name.as_bytes()) {
                return Ok(i as usize);
            }
        }
        Err(Error::InvalidColumnName(name.to_string()))
    }