title: tsc and nested tsconfigs
body: <p>TS 3.5
  I have the following config that works fine with tsserver during development:</p>
  
  <pre><code>/tsconfig.json &lt;= "strict": true
    /nested/tsconfig.json &lt;= extends parent tsconfig, "noImplicitThis": false
    /nested/some ts code &lt;= has implicit this
  </code></pre>
  
  <p>So my parent config defines strict true, and most code in the project alings with this rule. But in folder called <code>nested</code> there is a code that doesn't comply whit <code>noImplicitThis</code>, so I add there <code>tsconfig.json</code> that <code>extends</code> parent <code>tsconfig</code> and has compilerOption <code>noImplicitThis</code> set to <code>false</code>.</p>
  
  <p>And I get no error while development with <code>vscode</code>.</p>
  
  <p>But when I try to do <code>tsc -p .</code> (in the root dir) I get the error of "implicit this" in <code>nested</code> folder code.</p>
  
  <p>So I don't get how to make this nested/tsconfig.json to be applied to <code>nested/**</code> code while compilation of the whole project with <code>tsc</code>.</p>