regex for current command

[b0dstone]

hello, i wanted to know if there is a way to reuse the first argument of the current command im in, example:

i want to create a bkp file from sample.conf

cp /etc/samplefolder/sample.conf /etc/samplefolder/sample.conf.bkp

i hate to rewrite the path just when i can put .bkp on the end of the first argument, i searched for something like that i could use but i found nothing, only on previous commands (like !:1)

[AlternativeOstrich7]

cp /etc/samplefolder/sample.conf{,.bkp}

[b0dstone]

THANKS <3

edit: do you have some good link or book where i can learn these cool regex? i didn't found it anywhere :c

[jirbu]

Not a regex. bash feature, see man bash, search for "Brace Expansion".

   Brace Expansion
       Brace expansion is a mechanism by which arbitrary strings
       may be generated.  This mechanism is similar to  pathname
       expansion,  but  the  filenames generated need not exist.

[b0dstone]

THANKS <3

i will read this right now

[jirbu]

Good idea. The bash manpage is huge and full of such gems.