      let query = args[1].clone();
        let filename = args[2].clone();

        let case_sensitive = env::var(&quot;CASE_INSENSITIVE&quot;).is_err();

        Ok(Config { query, filename, case_sensitive })
    }
}</code></pre>
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<span class="caption">Listing 13-24: Reproduction of the `Config::new` function
from Listing 12-23</span>
-->
<p><span class="caption">リスト13-24: リスト12-23から<code>Config::new</code>関数の再現</span></p>
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At the time, we said not to worry about the ineff