Invert

[jaikishantulswani]

@ysf It would be good if it have invert match functionality too which is not in anew.

[ysf]

Do you have an example on what you'd like to invert? Thank you!

[jaikishantulswani]

@ysf suppose you sometimes need to append only the new list of contents to the file but sometime you also want to get the list of contents which are not matched like grep -vf

[kpcyrd]

@jaikishantulswani can you show some examples how it's supposed to behave? If I understood you right you're looking for something like this:

$ cat foo1.txt
a
b
c
$ anewer --invert foo1.txt # no output because no duplicates
$ cat foo2.txt
a
b
c
c
$ anewer --invert foo2.txt # the c line is in there twice, so we print the duplicate line
c
$ cat foo3.txt
a
b
b
c
c
c
$ anewer --invert foo3.txt # if the line is duplicated multiple times we're also going to show it multiple times
b
c
c

[jaikishantulswani]

@ysf I would like to get a feature like grep -vf, like the below example :

# cat foo1.txt 
a
b
c
d
# cat foo2.txt 
a
b
c
d
e
f
# cat foo2.txt | grep -vf foo1.txt 
e
f

[ysf]

@ysf I would like to get a feature like grep -vf, like the below example :

# cat foo1.txt 
a
b
c
d
# cat foo2.txt 
a
b
c
d
e
f
# cat foo2.txt | grep -vf foo1.txt 
e
f

But this is exactly what anewer does already:

cat foo2.txt | anewer foo1.txt e f

Are you sure you don't mean it the way kpcyrd says?

[ysf]

Either way, I just added an invert parameter like grep has it :)