Find similar lines in two text files?

Question

I have two sorted text files that are filled with python modules and version numbers. In this format:

Cython==0.21
DataShape==0.3.0
Flask==0.10.1
Jinja2==2.7.3
MarkupSafe==0.23
PIL==1.1.7

I want to compare and see what they have in common.

I know this will give me what they have exactly in common

comm -12 file1 file2

But I also want to know what modules they have in common, even if the version numbers are different. Is there any easy way to do this?

Answer 1

If it does not necessary have to be a one line command, you can use sed

sed 's/=.*//g' file1 > file1.stripped
sed 's/=.*//g' file2 > file2.stripped
comm -12 file1 file2

Answer 2

Since you are apparently in Linux, you can sed, sort, and uniq them (this depends on bash process subsntitution, you can write the intermittent files out if you need to):

diff <(awk -F= '{ print $1 }' firstfile.txt | sort | uniq) <(awk -F= '{ print $1 }' secondfile.txt | sort | uniq)

Answer 3

So I couldn't find a specific command, so I just wrote a quick python script to parse the file and give me only the parts before the "=", and then used comm to compare those new files.