Feature request: testline(tl) (RFC)

[V.Krishn]

Hi,

Was reading about bloom filter,
and came upon this example,

http://troydhanson.github.io/misc/bloom.html
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The bf test program

The program bf.c implements a Bloom filter. It can be used like,

./bf -n 16 members.txt test.txt

Where the lines of members.txt are the true set members and the lines of 
test.txt will be tested for membership. Varying n shows how the error rate 
increases with smaller values of n.
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Source: https://github.com/troydhanson/misc
code: 
https://raw.githubusercontent.com/troydhanson/misc/master/compression/bloom/bf.c

REQUEST:
Wondering if a simple implementation to test lines could be added to coreutils
Features:
1. report if some lines missing (option to print)
2. option to print found lines
3. option to print missing lines
4. ....more logic posible...

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Presently, I can achive the same using simple shell script by calling grep on 
each line or using `comm`
But believe that method using bloom should be faster and result in a uniq and 
useful tool.

Please ignore or guide if any similar util already exists.

-- 
Regards.
V.Krishn
(Insteps.net)