title: What is the difference between SPAN_POINT_MARK and SPAN_MARK_POINT?
body: <p>I have been reading up on the docs for the <a href="http://developer.android.com/reference/android/text/Spanned.html" rel="noreferrer" title="Spanned | Android Developers">Spanned/Spannable</a> class for a project that I am working on. I have been puzzled by the definition and usage of the spans that contain <code>MARK</code> and <code>POINT</code>.</p>
  
  <p>A <code>MARK</code> seems to be defined in the Doc as "attached" to a character's location while a <code>POINT</code> is defined as being "glued" to a character. Thus a <code>MARK</code> won't move when text is changed and a <code>POINT</code> will move with the character it was "glued" to when text is changed.</p>
  
  <p>These definitions seem to show that <code>MARK</code> is synonymous with <code>INCLUSIVE</code> and that <code>POINT</code> is synonymous with <code>EXCLUSIVE</code>.</p>
  
  <p>However, this is not the case as neither <code>SPAN_MARK_MARK</code> nor <code>SPAN_POINT_POINT</code> are synonymous with either <code>SPAN_INCLUSIVE_INCLUSIVE</code>or <code>SPAN_EXCLUSIVE_EXCLUSIVE</code>.  In fact, <code>SPAN_INCLUSIVE_INCLUSIVE</code> is the same as <code>SPAN_MARK_POINT</code> and <code>SPAN_POINT_MARK</code> is the same as <code>SPAN_EXCLUSIVE_EXCLUSIVE</code>.</p>
  
  <p>My questions are as follows</p>
  
  <ol>
  <li><p>Why is <code>SPAN_POINT_MARK</code> synonymous with <code>SPAN_EXCLUSIVE_EXCLUSIVE</code>? and why is <code>SPAN_MARK_POINT</code> synonymous with <code>SPAN_INCLUSIVE_INCLUSIVE</code>?</p></li>
  <li><p>Why aren't <code>SPAN_MARK_MARK</code> and <code>SPAN_POINT_POINT</code> synonymous with <code>SPAN_INCLUSIVE_INCLUSIVE</code>and <code>SPAN_EXCLUSIVE_EXCLUSIVE</code> respectively?</p></li>
  <li><p>What are the true definitions of <code>MARK</code> and <code>POINT</code> in this usage?</p></li>
  </ol>