title: alias not recognized if alias command is piped to bash
body: <p>I want to execute a small script by piping it into bash to execute it remotely without the need to copy. Everything seems to work except aliases:</p>
  
  <pre><code>echo "alias test_alias=\"echo alias\"; test_alias" | bash
  bash: line 1: test_alias: command not found
  </code></pre>
  
  <p>Does anyone know why this fails?</p>