From mboxrd@z Thu Jan  1 00:00:00 1970
From: Luke Diamand <luke@diamand.org>
Subject: Tilde spec - befuzzled
Date: Tue, 28 Feb 2012 09:07:41 +0000
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The documentation for caret and tilde specs is making my head hurt, even 
though they always _do_ exactly what I want. And I thought I understood 
them until I read more carefully.

   A suffix '{caret}' to a revision parameter means the first parent of
   that commit object.  '{caret}<n>' means the <n>th parent (i.e.
   '<rev>{caret}'

So far, so good.

'<rev>{tilde}<n>', e.g. 'master{tilde}3'::
   A suffix '{tilde}<n>' to a revision parameter means the commit
   object that is the <n>th generation grand-parent of the named
   commit object, following only the first parents.

Hang on, *grand*-parents?

So HEAD~1 won't give me the *parent* commit of HEAD, but the 
*grandparent* commit of HEAD (following only the first parents) ?

How do I get to the *parent* commit of HEAD?
Does that mean that HEAD~ != HEAD^
And why does HEAD~1 always look exactly what I would naively call the 
'parent' of HEAD?

I'm pretty sure I'm missing something very obvious. I think it must 
confuse other people as well though, as it's quite easy to find webpages 
around that claim that tildes give the _parent_ commit.

Thanks
Luke