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0 pointsmthoms4y ago0 comments

Google the phrase "useless use of cat".

To some, it's a faux-pas. Personally, I like the aesthetics of cat for my own scripts. It follows the "pipe flowing" idiom better.

There are performance reasons why "useless cat" should be avoided though. So avoid it where performance is important (or when some other hardcore CLI jockey is going to see your code :))

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2 comments · 2 top-level

bofh234y ago

Avoiding “useless cat” on the command line is premature optimization. Sure, don’t do it in a script that is invoked a lot but it shouldn’t be a concern when prototyping a filter pipeline.

  $ cat foo | head -4
  b
  a
  c
  b
  
  $ cat foo | head -4 | sort
  a
  b
  b
  c
  
  $ cat foo | head -4 | sort | uniq -c
  1 a
  2 b
  1 c
  
  $ cat foo | head -4 | sort | uniq -c | sort -k1nr | head -1
  2 b

hibbelig4y ago

I understand that people say you can replace

    foo < bar

with

    <bar foo

but I've never been able to get myself to do this.

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