Lynn,
For one or two topics, this is manageable.
I would use conditional build tags, as many of our colleagues
have done many times..
For simplicity, let's say we have just one topic with two
versions.
Call the original topica_v1.htm. Make a duplicate with a
filename topica_v2. Revise as necessary.
Assign a conditional build tag V! to the original and V2 to
the revision. Create a single source WebHelp layout that excludes
topics tagged V1, and another that excludes topics tagged V2.
Put both files into the Table of Contents. Assuming they have
the same title (it might be wise to change the title in some subtle
way), it will appear in the project as though the TOC has a
duplicate entry. However, when you generate WebHelp, the TOC will
not list the omitted file. There's some question about how the
Index and search will behave; test this.
I try to avoid duplicating topics because it seems to veer
away from single-source production.
This could get complicated. If you want to have another
version you can copy one (depending on where you want to start) and
tag it V3.
Stay with the exclusion approach to the output. In other
words,
not V1 and not V3
will allow V2 to go in.
not V2 and not V3
lets V1 get in.
Avoid this kind of Boolean phrase:
V2 and not V1 and not V3.
not V1 and V2 and not V3
Theoretically, either of these should omit V1 and V3, and put
out V2 (plus everything else, tagged or not). RoboHelp will let you
set it up this way, but apparently can't handle the logic when
generating WebHelp or printed documentation. I haven't tried parens
( ) in the Boolean string.
Here's an approach I've used successfully for a three-version
output.
Instead of duplicating a topic, and assuming the
corresponding topics have something in common, put all of the text
into one topic, and tag words and paragraphs as needed. Untagged
material comes through for everyone. I've done this with single
words, phases, entire paragraphs, graphics, template headers, and
tables.
(There's a little wrinkle with tables showing blank rows
where text is omitted, but I use a simple workaround to omit those
rows.)
The challenge here is managing the conditional parts as you
create more and more variations. RH conditional highlighting is
useful for tracking the pieces. You can turn conditional
highlighting off, which I do from time to time because I can miss
small typos behind the colors.
I hope this is useful.
Harvey