I have an SVN file which is now missing some logic and so I need to go back about 40 revisions to the time when it had the logic I need. Other than trying to view a diff of the file in the command line (very hard to read), is there any way I could get a copy of that file to review so I can study it to recover parts?
I believe the best way to view revisions is to use a program/app that makes it easy for you. I like to use trac : http://trac.edgewall.org/wiki/TracSubversion
It provides a great svn browser and makes it really easy to go back through your revisions.
It may be a little overkill to set this up for one specific revision you want to check, but it could be useful if you're going to do this a lot in the future.
Update to a specific revision:
svn up -r1234 file
Using the latest versions of Subclipse, you can actually view them without using the cmd prompt. On the file, simply right-click => Team => Switch to another branch/tag/revision. Besides the revision field, you click select, and you'll see all the versions of that file.
To directly answer the question of how to "get a copy of that file":
svn cat -r 666 file > file_r666
then you can view the newly created file_r666 with any viewer or comparison program, e.g.
kompare file_r666 file
nicely shows the differences.
I posted the answer because the accepted answer's commands do actually not give a copy of the file and because svn cat -r 666 file | vim does not work with my system (Vim: Error reading input, exiting...)
It is also interesting to compare the file of the current working revision with the same file of another revision.
You can do as follows:
$ svn diff -r34 file
Source: Stackoverflow.com