NAME

dec-pl - Decrement variable using Perl's auto-decrement notion

VERSION

This document describes version 0.001 of dec-pl (from Perl distribution App-IncrementUtils), released on 2019-01-25.

SYNOPSIS

 % dec-pl B b00 2.3
 A
 a99
 1.3

DESCRIPTION

This very simple script decrements its arguments using Perl module Data::Decrement, which basically tries to provide the counterpart to Perl's ++ (auto-increment) operator. The auto-increment rules, taken from perlop and copied here for convenience, are the following:

 The auto-increment operator has a little extra builtin magic to it. If you
 increment a variable that is numeric, or that has ever been used in a numeric
 context, you get a normal increment. If, however, the variable has been used in
 only string contexts since it was set, and has a value that is not the empty
 string and matches the pattern "/^[a-zA-Z]*[0-9]*\z/", the increment is done as
 a string, preserving each character within its range, with carry:

     print ++($foo = "99");      # prints "100"
     print ++($foo = "a0");      # prints "a1"
     print ++($foo = "Az");      # prints "Ba"
     print ++($foo = "zz");      # prints "aaa"

 "undef" is always treated as numeric, and in particular is changed to 0 before
 incrementing (so that a post-increment of an undef value will return 0 rather
 than "undef").

 The auto-decrement operator is not magical.

OPTIONS

--times=i (-n)

Specify how many times to decrement.

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/App-IncrementUtils.

SOURCE

Source repository is at https://github.com/perlancar/perl-App-IncrementUtils.

BUGS

Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=App-IncrementUtils

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.

SEE ALSO

Data::Decrement

AUTHOR

perlancar <perlancar@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2019 by perlancar@cpan.org.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.