request for enhancement: annotate

[Kevin Rodgers]

Would it be feasible to implement an RCS version of the CVS annotate
command?  If the same output could be generated, then the Emacs
vc-annotate command could use the same backend for RCS as for CVS.

Here are the descriptions of the CVS annotate command and the Emacs
vc-annotate command from their Info manuals:

| Annotate command
| ================
| 
|  - Command: cvs annotate [`-flR'] [`-r rev'|`-D date'] files ...
|      For each file in FILES, print the head revision of the trunk,
|      together with information on the last modification for each line.
|      For example:
| 
|           $ cvs annotate ssfile
|           Annotations for ssfile
|           ***************
|           1.1          (mary     27-Mar-96): ssfile line 1
|           1.2          (joe      28-Mar-96): ssfile line 2
| 
|      The file `ssfile' currently contains two lines.  The `ssfile line
|      1' line was checked in by `mary' on March 27.  Then, on March 28,
|      `joe' added a line `ssfile line 2', without modifying the `ssfile
|      line 1' line.  This report doesn't tell you anything about lines
|      which have been deleted or replaced; you need to use `cvs diff'
|      for that (*note diff::.).
| 
| 
|    The options to `cvs annotate' are listed in *Note Invoking CVS::,
| and can be used to select the files and revisions to annotate.  The
| options are described in more detail in *Note Common options::.

| Examining And Comparing Old Versions
| ====================================
| 
|    One of the convenient features of version control is the ability to
| examine any version of a file, or compare two versions.
...
| 
| `C-x v g'
|      Display the result of the CVS annotate command using colors.
...
|    For CVS-controlled files, you can display the result of the CVS
| annotate command, using colors to enhance the visual appearance.  Use
| the command `M-x vc-annotate' to do this.  It creates a new buffer to
| display file's text, colored to show how old each part is.  Text
| colored red is new, blue means old, and intermediate colors indicate
| intermediate ages.  By default, the time scale is 360 days, so that
| everything more than one year old is shown in blue.
| 
|    When you give a prefix argument to this command, it uses the
| minibuffer to read two arguments: which version number to display and
| annotate (instead of the current file contents), and a stretch factor
| for the time scale.  A stretch factor of 0.1 means that the color range
| from red to blue spans the past 36 days instead of 360 days.  A stretch
| factor greater than 1 means the color range spans more than a year.

-- 
Kevin Rodgers