script fails but succeeds in debugger

codeacrobat has asked for the wisdom of the Perl Monks concerning the following question:

Hello monks, I have experienced the phenomenon, that scripts with the latest Getopt::Long::Descriptive succeed in the debugger, but fail without. Can anyone explain why this happens or how to debug/fix these kind of issues?

> perl -v

This is perl, v5.10.1 (*) built for i686-cygwin-thread-multi-64int
(with 13 registered patches, see perl -V for more detail)

# try the Getopt::Long::Descriptive Synopsis
> perl synopsis.pl --help
Reference found where even-sized list expected at /usr/lib/perl5/site_
+perl/5.10/Getopt/Long/Descriptive.pm line 442.
Use of uninitialized value $arg{"name"} in hash element at /usr/lib/pe
+rl5/site_perl/5.10/Getopt/Long/Descriptive.pm line 477.
Use of uninitialized value in anonymous hash ({}) at /usr/lib/perl5/si
+te_perl/5.10/Getopt/Long/Descriptive.pm line 486.
Use of uninitialized value $arg{"name"} in hash element at /usr/lib/pe
+rl5/site_perl/5.10/Getopt/Long/Descriptive.pm line 503.
Reference found where even-sized list expected at /usr/lib/perl5/site_
+perl/5.10/

# works
> env PERLDB_OPTS="NonStop=1" perl -d synopsis.pl --help
my-program [-psv] [long options...] <some-arg>
        -s --server     the server to connect to
        -p --port       the port to connect to

        -v --verbose    print extra stuff
        --help          print usage message and exit
[download]

SOLVED A fresh reinstall of Params::Validate solved the issue.

print+qq(\L@{[ref\&@]}@{['@'x7^'!#2/"!4']});

Comment on script fails but succeeds in debugger Select or Download Code

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Re: script fails but succeeds in debugger by Anonyrnous Monk (Hermit) on Dec 20, 2010 at 11:21 UTC
Can't reproduce the issue, i.e. it works fine for me without the debugger: `#!/usr/bin/perl -w use strict; use Getopt::Long::Descriptive; my ($opt, $usage) = describe_options( 'my-program %o <some-arg>', [ 'server\|s=s', "the server to connect to" ], [ 'port\|p=i', "the port to connect to", { default => 79 } ], [], [ 'verbose\|v', "print extra stuff" ], [ 'help', "print usage message and exit" ], ); print($usage->text), exit if $opt->help;` [download] `$ ./877972.pl --help my-program [-psv] [long options...] <some-arg> -s --server the server to connect to -p --port the port to connect to -v --verbose print extra stuff --help print usage message and exit` [download] (tested with v5.10.1 () built for x86_64-linux-thread-multi) Update:* as the first problem happens here: `sub _validate_with { my (%arg) = validate(@_, { # <-- line 442 name => 1, params => 1, spec => 1, opts => 1, usage => 1, });` [download] and `validate()` is from Params::Validate, maybe there's some problem with this module? Which version are you using? (0.95 here)	[reply] [d/l] [select]
Re^2: script fails but succeeds in debugger by codeacrobat (Chaplain) on Dec 20, 2010 at 12:02 UTC
Ok it was Params::Validate. A fresh reinstall fixed the issue. I still would like to know how to better debug this issue. `print+qq(\L@{[ref\&@]}@{['@'x7^'!#2/"!4']});`	[reply] [d/l]
Re^2: script fails but succeeds in debugger by codeacrobat (Chaplain) on Dec 20, 2010 at 11:44 UTC
Hi. I have the latest version. `> perl -MParams::Validate -e 'print Params::Validate->VERSION' 0.95` [download] `print+qq(\L@{[ref\&@]}@{['@'x7^'!#2/"!4']});`	[reply] [d/l] [select]
Re: script fails but succeeds in debugger by mr_mischief (Monsignor) on Dec 20, 2010 at 12:05 UTC
Like Anonyrnous Monk (clever name, by the way), I cannot duplicate the problem. I tried with 5.10.1, 5.12.2, and 5.13.4 on Linux. Perhaps it's a problem with the Cygwin Perl? I suppose I could hook up a Windows box to see, but I'm sure none of my Cygwin installations are current. Do you have Strawberry Perl or ActiveState Perl installed with which to test? `This is perl, v5.10.1 (*) built for x86_64-linux-thread-multi (with 1 registered patch, see perl -V for more detail)` [download] `This is perl 5, version 12, subversion 2 (v5.12.2) built for x86_64-li +nux-ld` [download] `This is perl 5, version 13, subversion 4 (v5.13.4) built for x86_64-li +nux-ld` [download]	[reply] [d/l] [select]
Re: script fails but succeeds in debugger by Anonymous Monk on Dec 20, 2010 at 11:10 UTC
Could you show us the your code?	[reply]
Re: script fails but succeeds in debugger by codeacrobat (Chaplain) on Dec 20, 2010 at 11:39 UTC
`use Getopt::Long::Descriptive; my ($opt, $usage) = describe_options( 'my-program %o <some-arg>', [ 'server\|s=s', "the server to connect to" ], [ 'port\|p=i', "the port to connect to", { default => 79 } ], [], [ 'verbose\|v', "print extra stuff" ], [ 'help', "print usage message and exit" ], ); print($usage->text), exit if $opt->help;` [download] `print+qq(\L@{[ref\&@]}@{['@'x7^'!#2/"!4']});`	[reply] [d/l] [select]
Re^2: script fails but succeeds in debugger by Anonymous Monk on Dec 20, 2010 at 12:00 UTC
It works here: [~] perl -v \| grep built This is perl, v5.10.1 (*) built for i686-cygwin-thread-multi-64int [~] perl -MGetopt::Long::Descriptive -E'say$Getopt::Long::Descriptive: +:VERSION' 0.087 [~] perl -MParams::Validate -E'say$Params::Validate::VERSION' 0.95 [~] perl -c 877988.pl 877988.pl syntax OK [~] perl 877988.pl [~] perl 877988.pl --help my-program [-psv] [long options...] <some-arg> -s --server the server to connect to -p --port the port to connect to -v --verbose print extra stuff --help print usage message and exit [~] [download]	[reply] [d/l]