title: What is the @InlineOnly annotation?
body: <p>I <a href="https://github.com/JetBrains/kotlin/blob/master/libraries/stdlib/src/kotlin/io/Console.kt" rel="noreferrer">often</a> <a href="https://github.com/JetBrains/kotlin/blob/master/libraries/stdlib/src/kotlin/text/Charsets.kt#L13" rel="noreferrer">see</a> <a href="https://github.com/JetBrains/kotlin/blob/master/libraries/stdlib/src/kotlin/text/regex/RegexExtensions.kt" rel="noreferrer">the</a> <a href="https://github.com/JetBrains/kotlin/blob/master/libraries/stdlib/src/kotlin/internal/Annotations.kt#L60" rel="noreferrer"><code>@InlineOnly</code></a> annotation when browsing Kotlin's stdlib. As far as I recall the annotation only happens to be on <code>inline</code> functions. What is the purpose of this annotation? Isn't it obvious that <code>inline</code> functions are always inlined? It's documentation isn't really helpful</p>
  
  <blockquote>
    <p>Specifies that this function should not be called directly without inlining</p>
  </blockquote>
  
  <p>Is it possible for inline functions to be called not inline?</p>