branch 'blabla' then '@\{1\}' means the same as 'blabla@\{1\}'.
'@\{-<n>\}', e.g. '@\{-1\}'::
- The construct '@\{-<n>\}' means the <n>th branch checked out
+ The construct '@\{-<n>\}' means the <n>th branch/commit checked out
before the current one.
'<branchname>@\{upstream\}', e.g. 'master@\{upstream\}', '@\{u\}'::