in reply to Golf: reverse sort /etc/passwd by UID

Only suitable for a terminal, not to be redirected to a file: 
#                 1         2         3         4
#        12345678901234567890123456789012345678901234
perl -e 'print sort map 9/(1+(split/:/)[2])."\r$_",<>' /etc/passwd

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لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

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Re^2: Golf: reverse sort /etc/passwd by UID
by tobyink (Canon) on Feb 06, 2013 at 22:11 UTC

    Nice, but one of the lines in my /etc/passwd file comes out as:

    1.52590218966964e-05\rnobody:x:65534:65534:nobody:/nonexistent:/bin/sh

    [download]

    And thus gets sorted after root.

    package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name
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      OK, just change 1/ to 9/ (or 8 or 7). Updated.
      لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ
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Re^2: Golf: reverse sort /etc/passwd by UID
by MidLifeXis (Monsignor) on Feb 06, 2013 at 18:02 UTC

    Cool (and sneaky)!

    Nice use of the features of how floats are printed and the behavior of a console. Could this run into problems with a very short passwd line?

    1. Takes the third field
    2. Adds one to avoid div by 0
    3. Inverts it (1/X) to get the sort order correct
    4. appends a carriage return (beginning of line)
    5. appends the original line
    6. sorts numerically lexically, but with all values being less than 1 it does not make a difference.
    7. prints results

    Update: Updated how sort happens.

    Update 2: s/<ul>/<ol>/

    --MidLifeXis

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      I'm not clear on how it sorts on a field in the text while at the same time appending the text to the field which is sorted. What am I missing here?

      Tommy
      A mistake can be valuable or costly, depending on how faithfully you pursue correction
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        at the same time
        Nothing is happening at the same time. The steps shown by MidLifeXis are ordered (maybe <ol> would have been better than <ul>). First, the text is concatenated, then it is sorted.
        لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ
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Re^2: Golf: reverse sort /etc/passwd by UID
by Tommy (Chaplain) on Feb 06, 2013 at 17:24 UTC

    Good gosh, can't even decipher that. Sorting the output of a map applying a mathematical expression to the list of lines on STDIN... but how do you discard the text it generated here --> (1+(split/:/)[2])<-- ??

    Tommy
    A mistake can be valuable or costly, depending on how faithfully you pursue correction
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