NAME

L - Greple module to produce result by line numbers

SYNOPSIS

greple -ML

VERSION

Version 1.01

DESCRIPTION

This module allows you to use line numbers to specify patterns or regions which can be used in greple options.

• -ML line numbers

  If a line number argument immediately follows -ML module option, it is recognized as a line number. Note that, this format implicitly adds the --cm N option to disable the coloring feature. Use the --cm @ option to cancel it.

  Next command will show 42nd line.

    greple -ML 42 file
  

  Multiple lines can be specified by joining with comma:

    greple -ML 42,52,62
  

  Range can be specified by colon:

    greple -ML 42:84
  

  You can also specify the step with range. Next command will print all even lines from line 10 to 20:

    greple -ML 10:20:2
  

  Any of them can be omitted. Next commands print all, odd and even lines.

    greple -ML ::    # all lines
    greple -ML ::2   # odd lines
    greple -ML 2::2  # even lines
  

  If start and end number is negative, they are subtracted from the maxmum line number. If the end number is prefixed by plus (`+') sign, it is summed with start number. Next commands print top and last 10 lines respectively.

    greple -ML :+9   # top 10 lines
    greple -ML -9:   # last 10 lines
  

  If forth parameter is given, it describes how many lines is included in that step cycle. For example, next command prints top 3 lines in every 10 lines.

    greple -ML ::10:3
  

  When step count is omitted, forth value is used if available. Next command print every 10 lines in group.

    greple -ML :::10 --blockend=-- /etc/services
  

• -L=line numbers

  -L is an option to explicitly specify line numbers. All of the above commands can be specified using the -L option. The only difference is that the coloring feature is not automatically disabled.

    greple -ML -L 42
    greple -ML -L 10:20:2
    greple -ML -L :+9
  

  -L option can be used multiple times, like:

    greple -ML -L 42 -L 52 -L 62
  

  But this command produce nothing, because each line definitions are taken as a different pattern, and greple prints lines only when all patterns matched. You can relax the condition by --need 1 option in such case, then you will get expected result. Next example will display 42nd, 52nd and 62nd lines in different colors.

    greple -ML -L 42 -L 52 -L 62 --need 1
  

  Next example print all lines of the file, each line in four different colors.

    greple -ML -L=1::4 -L=2::4 -L=3::4 -L=4::4 --need 1
  

• L=line numbers

  This notation just define function spec, which can be used in patterns, as well as blocks and regions. Actually, -L=line is equivalent to --le L=line.

  Next command show patterns found in line number 1000-2000 area.

    greple -ML --inside L=1000:+1000 pattern
  

  Next command prints all 10 line blocks which include the pattern.

    greple -ML --block L=:::10 pattern
  

  In this case, however, it is faster and easier to use regex.

    greple --block '(.*\n){1,10}' pattern
  

• --offload=command

  Set the offload command to retrieve the desired line numbers. The numbers in the output, starting at the beginning of the line, are treated as line numbers. This is compatible with grep -n output.

  Next command print 10 to 20 lines.

    greple -ML --offload 'seq 10 20'
  

Using this module, it is impossible to give single L in command line arguments. Use like --le=L to search letter L. You have a file named L? Stop substitution by placing -- before the target files.

INSTALL

CPANMINUS

$ cpanm App::Greple::L

GITHUB

$ cpanm https://github.com/kaz-utashiro/greple-L.git

SEE ALSO

App::Greple, https://github.com/kaz-utashiro/greple

Getopt::EX::Numbers

AUTHOR

Kazumasa Utashiro

LICENSE

Copyright 2014-2025 Kazumasa Utashiro.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.