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В статье "More one-line Perl scripts" приводится десятки примеров однострочных (вида, perl -e 'code') скриптов на Perl, которые могут оказаться полезными для решения рутинных задач.
Вообще, написание небольших однострочных скриптов требует особенного подхода, статья интересная, вот несколько примеров:
вывод столбцов, как awk
perl -lane 'print $F[0] + $F[-2]'
вывод строк из промежутка.
# 1. just lines 15 to 17
perl -ne 'print if 15 .. 17'
# 2. just lines NOT between line 10 and 20
perl -ne 'print unless 10 .. 20'
# 3. lines between START and END
perl -ne 'print if /^START$/ .. /^END$/'
# 4. lines NOT between START and END
perl -ne 'print unless /^START$/ .. /^END$/'
поиск и замена, как sed
# 1. in-place edit of *.c files changing all foo to bar
perl -p -i.bak -e 's/\bfoo\b/bar/g' *.c
# 2. delete first 10 lines
perl -i.old -ne 'print unless 1 .. 10' foo.txt
# 3. change all the isolated oldvar occurrences to newvar
perl -i.old -pe 's{\boldvar\b}{newvar}g' *.[chy]
# 4. increment all numbers found in these files
perl -i.tiny -pe 's/(\d+)/ 1 + $1 /ge' file1 file2 ....
# 5. delete all but lines between START and END
perl -i.old -ne 'print unless /^START$/ .. /^END$/' foo.txt
# 6. binary edit (careful!)
perl -i.bak -pe 's/Mozilla/Slopoke/g' /usr/local/bin/netscape
вывод файлов задом-наперед
# 1. command-line that reverses the whole input by lines
perl -e 'print reverse <>' file1 file2 file3 ....
# 2. command-line that shows each line with its characters backwards
perl -nle 'print scalar reverse $_' file1 file2 file3 ....
# 3. find palindromes in the /usr/dict/words dictionary file
perl -lne '$_ = lc $_; print if $_ eq reverse' /usr/dict/words
# 4. command-line that reverses all the bytes in a file
perl -0777e 'print scalar reverse <>' f1 f2 f3 ...
# 5. command-line that reverses each paragraph in the file but prints them in order
perl -00 -e 'print reverse <>' file1 file2 file3 ....
переименование группы файлов
# 1. write command to mv dirs XYZ_asd to Asd
ls | perl -pe 's!([^_]+)_(.)(.*)!mv $1_$2$3 \u$2\E$3!gio'
# 2. Write a shell script to move input from xyz to Xyz
ls | perl -ne 'chop; printf "mv $_ %s\n", ucfirst $_;'
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