FYING REVISIONS above), you can ask
for commits that are reachable from r2 excluding those that are reachable
from r1 by <em>^r1 r2</em> and it can be written as <em>r1..r2</em>.</p>
</div>
<div class="paragraph">
<p>A similar notation <em>r1...r2</em> is called symmetric difference
of <em>r1</em> and <em>r2</em> and is defined as
<em>r1 r2 --not $(git merge-base --all r1 r2)</em>.
It is the set of commits that are reachable from either one of
<em>r1</em> or <em>r2</em> but not from both.</p>
</di