title: implicitly convert string to string_view
body: <pre><code>void Foo1(string_view view) {
  ... 
  }
  
  string str = &quot;one two three&quot;;
  
  Foo1(&quot;one two three&quot;); // Implicitly convert char* to string_view
  
  Foo1(str); 
  
  </code></pre>
  <p><a href="https://i.stack.imgur.com/attAw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/attAw.png" alt="enter image description here" /></a>
  I wonder which constructor converts char* to string_view implicitly and which one converts the string to string_view implicitly?</p>
  <p>I know constructor (4) convert const char* to string_view but what I passed is char*.</p>