[texhax] writing about 2 parallel developments of a product withthe same base code

[Philip G. Ratcliffe]

> Hi, can someone tell me how can I write 2 documents that have 90% of
> the content the same, the rest 10% modified, some sections added, some
> modified and some deleted?
> Basically I need to write about 2 parallel developments of a product
> with the same base code.

Simply put the content in separate subfiles and have two main files that
\input or \include (N.B. \include starts a new page) the various subfiles as
necessary.

Alternatively to maintain just a single main file, or if you wish to
interleave pieces for one or other document inside the subfiles, put

  \newif\ifdocA

in the main files' preambles, followed by either \docAtrue or \docAfalse
accordingly.

In your subfiles you can then simply put things like:

This product is \ifdocAtrue really wonderful\else absolutely useless\fi. We
\ifdocAtrue\else cannot \fi recommend it.

You can easily get more sophisticated if need be, but this should be good
enough for starters.

Cheers,  Phil Ratcliffe