Using RegEx to automerge text files

Question

I'm looking for a tool that will let me run a comparison on two files (A and B) and automatically copy changes from B to A if the text in B matches a regular expression. I've experimented with diff and WinMerge, but need something that will let me match lines rather than chunks. I've also tried Meld, but it did a very bad job of correlating the two texts (probably because Meld's text filters delete non-matching text and most of my text is non-matching).

For background/more details: I'm working on a digital humanities project, and am trying to merge two different versions of a lengthy historical text for an online edition. We have a nice, clean version with editorial apparatus that was printed and published, but ignores the page breaks in the original manuscripts; and we have a rougher transcript that does have the page-breaks but isn't as reliable and has been chewed up by our DAMS (the original transcript files have been lost so I had to re-export them). We're trying to put the cleaned-up text online next to scans of the original document, and I would love to just move all the page-breaks into the clean version text, but don't know how.

For a sense of what the texts look like, here's something in the style of A:

March 1. Went to the store and saw [John Smith]. Had a nice time.
March 2. Mowed the lawn.
March 3. Same.
March 4. Same.
March 5. Had lunch with [Richard Wainright].
March 6. Mowed the lawn.
March 7. Same.
March 8. Same.
March 9. Read [Shakespeare's] Hamlet.

The same text in the style of text B:

Mar 1. Went to teh store & saw John.
Had a nice tim.
Mar 2. Mow'd the lawn.
Mar 3. Same.
Mar 4. Same.

Mar 5. Had lunch with Dicky.
Mar 6. Mowed teh lawn.
Mar 7. Same.
<pagebreak>
Mar 8. Same.
Mar 9. Read Hamlet.

And the desired output:

March 1. Went to the store and saw [John Smith]. Had a nice time.
March 2. Mowed the lawn.
March 3. Same.
March 4. Same.
March 5. Had lunch with [Richard Wainright].
March 6. Mowed the lawn.
March 7. Same.
<pagebreak>
March 8. Same.
March 9. Read [Shakespeare's] Hamlet.

I've found that, e.g., the find differences tool in BBedit is very helpful at correlating the texts, but I want to be able to filter differences using RegEx.

Answer 1

BeyondCompare (see www.scootersoftware.com) has several ways including regular expressions to control which parts of lines are used or excluded when comparing files.

Not sure about the "automatic copy" aspect. However, BeyindCompare does have scripting facilities that may provide the automation sought.

The last time I looked it offered a 30-day free trial and after that the cost for a one-user licence is US$30 or US$60 depending on version. I found the program so useful at work that I bought my own personal copy.