# HG changeset patch
# User Anton Shestakov <av6@dwimlabs.net>
# Date 1590205406 -28800
# Node ID e5406605d8f5eb14a51e15db03e5b1e23414120c
# Parent  498dc93c3fa0742db7789afe7cd2a1b7e88e518c
topic: document the other safehasattr() compatibility check

diff -r 498dc93c3fa0 -r e5406605d8f5 hgext3rd/topic/revset.py
--- a/hgext3rd/topic/revset.py	Tue May 19 12:49:12 2020 +0800
+++ b/hgext3rd/topic/revset.py	Sat May 23 11:43:26 2020 +0800
@@ -107,6 +107,8 @@
         branch = repo[None].branch()
     return revset.baseset(stack.stack(repo, branch=branch, topic=topic)[1:]) & subset
 
+# x#y[z] revset operator support (no support for older version)
+# hg <= 4.8 (e54bfde922f2)
 if util.safehasattr(revset, 'subscriptrelations'):
     def stacksubrel(repo, subset, x, rel, z, order):
         """This is a revset-flavored implementation of stack aliases.