Documentation: user-manual: limit potentially confusing usage of 3dots (and 2dots)

Using them as continuation indications for abbreviated SHA-1 values
bears the risk that they are mistaken for the dotted range operators.

Commands which expect a single commit will fail when given a range of
commits.

Also, add a note that sometimes, 3dots are just continuation
indications.

Signed-off-by: Ann T Ropea <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: bedhanger

Documentation/user-manual.txt

@@ -319,7 +319,7 @@ do so (now or later) by using -b with the checkout command again. Example:
 
   git checkout -b new_branch_name
 
-HEAD is now at 427abfa... Linux v2.6.17
+HEAD is now at 427abfa Linux v2.6.17
 ------------------------------------------------
 
 The HEAD then refers to the SHA-1 of the commit instead of to a branch,
@@ -508,7 +508,7 @@ Bisecting: 3537 revisions left to test after this
 
 If you run `git branch` at this point, you'll see that Git has
 temporarily moved you in "(no branch)". HEAD is now detached from any
-branch and points directly to a commit (with commit id 65934...) that
+branch and points directly to a commit (with commit id 65934) that
 is reachable from "master" but not from v2.6.18. Compile and test it,
 and see whether it crashes. Assume it does crash. Then:
 
@@ -549,14 +549,14 @@ says "bisect".  Choose a safe-looking commit nearby, note its commit
 id, and check it out with:
 
 -------------------------------------------------
-$ git reset --hard fb47ddb2db...
+$ git reset --hard fb47ddb2db
 -------------------------------------------------
 
 then test, run `bisect good` or `bisect bad` as appropriate, and
 continue.
 
 Instead of `git bisect visualize` and then `git reset --hard
-fb47ddb2db...`, you might just want to tell Git that you want to skip
+fb47ddb2db`, you might just want to tell Git that you want to skip
 the current commit:
 
 -------------------------------------------------
@@ -3426,6 +3426,8 @@ Date:
 ...
 :100644 100644 oldsha... 4b9458b... M somedirectory/myfile
 ------------------------------------------------
+(Note that in the above, the "..." are used as continuation
+indications, not as symmetric difference operators!)
 
 This tells you that the immediately following version of the file was
 "newsha", and that the immediately preceding version was "oldsha".
@@ -3449,7 +3451,7 @@ and your repository is good again!
 $ git log --raw --all
 ------------------------------------------------
 
-and just looked for the sha of the missing object (4b9458b..) in that
+and just looked for the sha of the missing object (4b9458b) in that
 whole thing. It's up to you--Git does *have* a lot of information, it is
 just missing one particular blob version.
 
@@ -4114,9 +4116,9 @@ program, e.g.  `diff3`, `merge`, or Git's own merge-file, on
 the blob objects from these three stages yourself, like this:
 
 ------------------------------------------------
-$ git cat-file blob 263414f... >hello.c~1
-$ git cat-file blob 06fa6a2... >hello.c~2
-$ git cat-file blob cc44c73... >hello.c~3
+$ git cat-file blob 263414f >hello.c~1
+$ git cat-file blob 06fa6a2 >hello.c~2
+$ git cat-file blob cc44c73 >hello.c~3
 $ git merge-file hello.c~2 hello.c~1 hello.c~3
 ------------------------------------------------
 
@@ -4374,7 +4376,7 @@ $ git log --no-merges t/
 ------------------------
 
 In the pager (`less`), just search for "bundle", go a few lines back,
-and see that it is in commit 18449ab0...  Now just copy this object name,
+and see that it is in commit 18449ab0.  Now just copy this object name,
 and paste it into the command line
 
 -------------------