cargo : warning: struct is never constructed: `Config`
所在位置 行:1 字符: 1
+ cargo run poem.txt > output.txt 2> error.txt
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (warning: struct...ucted: `Config`:String) [], RemoteException
    + FullyQualifiedErrorId : NativeCommandError
 
 --> src\lib.rs:4:12
  |
4 | pub struct Config {
  |            ^^^^^^
  |
  = note: `#[warn(dead_code)]` on by default

warning: associated function is never used: `new`
  --> src\lib.rs:11:12
   |
11 |     pub fn new() -> Result<Config, &'static str> {
   |            ^^^

warning: function is never used: `run`
  --> src\lib.rs:24:8
   |
24 | pub fn run(config: Config) -> Result<(), Box<dyn Error>> {
   |        ^^^

warning: function is never used: `search`
  --> src\lib.rs:35:8
   |
35 | pub fn search<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
   |        ^^^^^^

warning: function is never used: `search_case_insensitive`
  --> src\lib.rs:41:8
   |
41 | pub fn search_case_insensitive<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
   |        ^^^^^^^^^^^^^^^^^^^^^^^

warning: `minigrep` (bin "minigrep") generated 5 warnings
    Finished dev [unoptimized + debuginfo] target(s) in 0.02s
     Running `target\debug\minigrep.exe poem.txt`
Problem parsing arguments! not enough arguments
error: process didn't exit successfully: `target\debug\minigrep.exe poem.txt` (exit code: 1)