Use bash history with process substitution

Bash has a great history system of its commands accessed by the ! built-in history expansion operator (documented elsewhere on this site or on the web). You can combine the ! operator inside the process redirection Very handy.
Sample Output
diff <(!!) <(!510)
diff <(ls | perl -ple 's/\..*$//' | sort) <(sort fnam.txt)
... diff output between the last command and command line 510

By: drewk
2010-02-06 18:35:10

What Others Think

Fantastic combination of history expansion and process substitution!
philiph · 645 weeks ago
I always thought this would be handy. Makes sense with the (). Thanks.
somaddict · 497 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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