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: error.rs
    path of file: ./repos/wasmer/tests/lib/wast/src
    
    the code of the file until where you have to start completion: use std::fmt;
use thiserror::Error;

/// A Directive Error
#[derive(Debug)]
pub struct DirectiveError {
    /// The line where the directive is defined
    pub line: usize,
    /// The column where the 
    
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        // Write strictly the first element into the supplied output
        // stream: `f`. Returns `fmt::Result` which indicates whether the
        // operation succeeded or failed. Note that `write!` uses syntax which
        // is very similar to `println!`.
        writeln!(f, "Failed directives on {}:", self.filename)?;
        for error in self.errors.iter() {
            writeln!(f, "  â€¢ {} ({}:{})", error.message, error.line, error.col)?;
        }
        Ok(())
    }