So I don't have to go searching for the specific paragraph in perldelta that you are referring to, how about pasting it into your question?

Should you worry about it? I think the answer is yes, if you feel you might be triggering an incompatibility, until you can prove through tests that you've handled it appropriately. How do you identify if it's a concern? Write a test, or a bunch of tests that prove your code does as intended before and after the upgrade.

See Test::More, and chromatic's Perl Testing: A Developer's Notebook, or Intermediate Perl for testing strategies.

Referenced perldelta entry

Should I worry about it.

Do you unpack text or just binary data. If the latter, probably no issues.

seeking

scandeps

perlver

minimum version

finding

scandeps.pl

found

perlver - The Perl Minimum Version Analyzer

Perl::MinimumVersion - Find a minimum required version of perl for Perl code

I don't think any of those can determine if the code relies on the buggy behaviour of 5.8's pack and unpack or not.

How to identify incompatible use of pack and unpack. And how to fix it for following examples if they are incompatible uses. I want to use code around it in perl 5.22. This is present in perl 5.8 currently and working fine. I dont know if it will break or work when I upgrade perl to v5.22

pack("$L", unpack("$L", $_)
sprintf("%08x", unpack("N",function($relay))); 
push(@rv, join('.', unpack("CCCC", function($i)))); 
unpack("u", $len . $1 ); 
unpack("w*", $v); 
unpack("V", $v) == 1
unpack("x$start_offset x4 $L$L$L$L$S$S$L$L", $file); 
unpack("x$d_off $S/a", $file); 
unpack("H*", shift); 
[download]

What is $L?

Can't debug pack/unpack templates that we can't see.

You should create a small segment of code starting with use strict, and ending with a __DATA__ tag that contains some sample data, and that demonstrates your packing and unpacking (which presumably aren't working as you intend), along with a good description of what you actually do intend. Self-contained. We should be able to run it and see the failure.




Dave

I don't think any of them will have any issues except possibility differences in warnings for bad data.

I know that pack changed how it handled some invalid inputs, but that's not relevant here.

Upd: Looks like you found a possible source of problems: Incompatibility after perl 5.10 packing and UTF-8 strings

> How to identify incompatible use of pack and unpack.

by writing tests, see Test::More etc.

Cheers Rolf
_{(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery}

This seems to be closely related to Incompatibility after perl 5.10 packing and UTF-8 strings. Why did you create a new thread?

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)