Sorry, I am trying to simplify things, and likely making them more complicated. :(

I think I can provide some sample data easier than I can change the code to make it work on the sample.

This is what the input would look like: 

 ref 1
 ref 2
 ref 3
 ref 4
begin
1
end
begin
2
bar
end
begin
3
end
begin
4
bar
end
 ref 5
 foo ref 6
 ref 7
begin
5
end
begin
6
bar
begin
7
bar
end

[download]

So I am trying to remove only the "ref n" lines (not the n lines themselves), and only for paragraphs where "bar" appears in the paragraph. The output should look like this: 

 ref 1
 ref 3
begin
1
end
begin
2
bar
end
begin
3
end
begin
4
bar
end
 ref 5
begin
5
end
begin
6
bar
begin
7
bar
end

[download]

So I do (think I) need to pass through the file twice - once to find the references I want to remove, and once to actually remove them.

In reply to Re^2: some efficiency, please by Anonymous Monk
in thread some efficiency, please by Anonymous Monk

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