A user asked for a (awk or similar) one-liner that would replace a separator by a different one in a file, but only the first N separators should be replaced.

For small Ns, it's easiest to repeat the substitution:

perl -pe 's/,/|/;s/,/|/;s/,/|/'
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But, what should one do when they want to replace the first 10 separators?

My first idea was to use a for loop:

perl -pe 's/,/|/ for 1 .. 10'  # Oops!
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Unfortunately, it doesn't work, as the for creates another local $_ and the substitution happens to the numbers, not the input.

So, my next idea was to use a counter with /e:

perl -pe 's/,/$i++<10 ? "|" : ","/ge'
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It works, but is ugly and hard to explain to someone not familiar with Perl.

Another way is to tie the two $_ variables together by aliasing the outer $_ by the inner one:

perl -pe 's/,/|/ for $_, $_'
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But, we can generalize a list of the same things: we can use the x operator in list context! It's short, readable, and follows the DRY principle:

perl -pe 's/,/|/ for ($_) x 10'
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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