Re: matching exact lines in files

[Alan Curry]

In article <ftOUg.4846$Y24.700@newsread4.news.pas.earthlink.net>,
Jim Showalter  <jshowalter@gmail.com> wrote:
>Specifically, I want is to find all lines in a.txt that match any of

So far, this sounds like a grep.

>the following three groups of lines in b.txt:
>
>1-0
>[Event "ICC"]
[snip]

>1-0
>
>[Event "ICC"]
>
>should not match because there is an intervening blank line.

Oh, a multi-line pattern. This does what you asked for:

perl -nle 'print "$prev\n$_" if $prev =~ m@^(1-0|0-1|1/2-1/2)$@ &&
                                $_ eq q/[Event "ICC"]/; $prev=$_' file

>Also, if anyone knows how I can accomplish this easily with vim, that
>would even be better.  But I have never been able to figure out how
>to include end-of-lines or blank-lines in vim searches.

I can search for newlines just fine with vim, using \n.

>Or maybe I have to use some other tools?

If I can guess your intent (rather than just giving you exactly what you
asked for), these are probably what you really want:

# Find all lines that exactly match [Event "ICC"] and print them, together
# with 1 preceding line.
grep -B 1 -Fx '[Event "ICC"]' file

# Same thing, then get rid of the [Event "ICC"] lines and the separators
# leaving only the lines that preceded the [Event "ICC"] lines
grep -B 1 -Fx '[Event "ICC"]' file |
  grep -Fxv -e '[Event "ICC"]' -e '--'

# Building on the previous example, group and count the occurrences of each
# result
grep -B 1 -Fx '[Event "ICC"]' file |
  grep -Fxv -e '[Event "ICC"]' -e '--' | sort | uniq -c

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