in reply to Re: Efficient way to replace a set of values with another set of values
in thread Efficient way to replace a set of values with another set of values

Command line version: 
perl -pi -e 's/^(\d)/chr($1+96)/e' myfile

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Re^3: Efficient way to replace a set of values with another set of values
by space_monk (Chaplain) on Nov 23, 2012 at 13:08 UTC
    Parent beat me to the one line solution, but perhaps a minor mod may be needed; I suspect that the OP may have numbers larger than just 1-6, so perhaps: 
    perl -pi -e 's/^(\d+)/chr($1+96)/e' myfile

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    A Monk aims to give answers to those who have none, and to learn from those who know more.
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[d/l]

      space_monk:

      OK, your solution is a bit better .... at least until you get to "27. This is a really long list!".

      ;^D

      ...roboticus

      When your only tool is a hammer, all problems look like your thumb.

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        ... until you get to "27. This is a really long list!".

        Maybe something like (and 'zz' could easily be 'zzz'): 

        >perl -wMstrict -e
"my @lines = (
   '1. This is just a sample.',
   '2. This is to check',
   '3. How a set of values',
   '4. can be replaced by another',
   '5. set of values and that too',
   '6. in the most efficient way.',
   '99. And also handle large numbers.',
   '999. Oops, too big!',
   '99 bottles of beer on the wall does not translate!',
   );
 ;;
 my %xlate;
 { my @alphas = (undef, 'a' .. 'zz');
   @xlate{ 1 .. $#alphas } = @alphas[ 1 .. $#alphas ];
   }
 ;;
 s{ \A (\d+) (?= [.]) }
  { exists $xlate{$1}
    ? $xlate{$1} : (warn(qq{bad '$1' in '$_'}), '??')
    }xmse
  for @lines;
 ;;
 print qq{$_\n} for @lines;
"
bad '999' in '999. Oops, too big!' at -e line 1.
a. This is just a sample.
b. This is to check
c. How a set of values
d. can be replaced by another
e. set of values and that too
f. in the most efficient way.
cu. And also handle large numbers.
??. Oops, too big!
99 bottles of beer on the wall does not translate!

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[d/l]

        Ha ha. I spent an inordinate amount of time trying to make a one-liner solution for arbitrarily large numbers (where it would go to "aa" after "z"). However, it turned out that today is Friday and I can't think that hard.



        When's the last time you used duct tape on a duct? --Larry Wall
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