[kwlug-disc] fish vs bash: a progress bar from YSAP and some timing measurements

[Ron]

Thanks, Evan @ GTALUG, for bringing fish shell to my attention. I'm 
really liking it - it's just what I needed and didn't even know it.


So, I'd mentioned it feeling faster, which William Park commented on. 
Thanks William, you got me thinking.


"Feels faster" ≠ "is faster" and I thought I'd measure something.


And along comes Dave from YSAP with a great video on how to make a 
progress bar in bash.

https://www.youtube.com/watch?v=aL3xdQyMs5o

I love his videos, he's highly knowledgeable and quite engaging. He make 
bash scripting look fun.


I decided to implement his idea without too much peeking at the 
solution, then re-implement it in fish.

Despite me saying earlier that I'd probably continue scripting in bash.


The fish syntax is *so much better*.

When I went to add a feature to the bash script, once again I got caught 
up in punctuation hell, where fish mostly eschews that inscrutable mess 
for things like:

$ math "10 * 5 / 100"
0.5

Note the floating point math...



When done, I ran them both with the `time` command, and bash version was 
consistently faster (results at bottom of message).


However, if one takes into account dev time, fish is faster despite it 
being new to me.

So it depends on how you rank run time vs dev time which is "faster", 
but I'm giving the win to fish in this case.


Adding to that the luxurious interactive features and it's a no-brainer: 
fish is the (my) future. The tab-completion is light years ahead of bash 
(but so is the tab completion in node.js, bash is kind of lagging behind 
here these days).





  $ time ./progress-bar.bash
START: files count: 500 Batch size: 3
   [||||||||||||||||||||||||||||||||||||||||||||||||||] 500/500 (100)%

________________________________________________________
Executed in    1.04 secs      fish           external
    usr time  115.62 millis  545.00 micros  115.08 millis
    sys time   58.08 millis  214.00 micros   57.87 millis


  $ time ./progress-bar.fish
START: files count:  500  Batch size: 3
   [||||||||||||||||||||||||||||||||||||||||||||||||||] 500/500 (100)%

________________________________________________________
Executed in    1.50 secs      fish           external
    usr time  490.80 millis    0.00 micros  490.80 millis
    sys time  148.81 millis  760.00 micros  148.05 millis