How can I find place of error in perl [duplicate]

Question

This question already has an answer here:

Expert system doesn't initialize (1 answer)

Compilation of perl script failed

Closed 9 years ago.

I tried to run AI::ExpertSystem::Advanced from CGI website. My server (xampp on localhost) have in log this error:

The system cannot find the path specified.

Unable to get Terminal Size. The Win32 GetConsoleScreenBufferInfo call didn't work. The COLUMNS and LINES environment variables didn't work. The resize program didn't work. at C:/Perl/lib/Term/ReadKey.pm line 362.
Compilation failed in require at C:/Perl/lib/Term/ReadLine/Perl.pm line 65.

How can I specify what path is bad? How can I find where is error???

Answer 1

The error messages in the question state that the error is thrown at C:/Perl/lib/Term/ReadKey.pm line 362 and that use Term::ReadKey appears at C:/Perl/lib/Term/ReadLine/Perl.pm line 65.

However, the comments to the question indicate that you are trying to run this code in a CGI environment. Given that the purpose of Readline is to provide additional functionality when reading a line of input from a terminal[*], it makes no sense to use it in a CGI context and I'm not at all surprised that it doesn't work there.

According to metacpan, AI::ExpertSystem::Advanced does not depend on Term::ReadLine::Perl, nor do any of its dependencies. Term::ReadLine::Perl must be getting used by some other part of your code. To resolve this problem, locate that section of code (grep -ir readline /my/source/tree) and change it to either not use Readline at all or to detect whether it is running on the command line or under CGI and only require Term::ReadLine::Perl if it's on the command line.

Edit: Tracking back through your earlier questions on this issue, I see that you're creating your ExpertSystem instance with viewer_class => 'terminal', which causes it to use AI::ExpertSystem::Advanced::Viewer::Terminal, which "Extends from AI::ExpertSystem::Advanced::Viewer::Base and its main purpose is to interact with a (console) terminal." (emphasis mine) In order to make this work, you need to use a different viewer class which does not "interact with a (console) terminal". Unfortunately, a search of metacpan finds no other available viewers, so you'll need to either find one somewhere else (the author of AI::ExpertSystem::Advanced may know where you can get one for CGI) or write your own viewer class.

[*] From the Term::ReadLine::Perl5 documentation:

GNU Readline reads lines from an interactive terminal with emacs or vi editing capabilities. It provides as mechanism for saving history of previous input.

This package typically used in command-line interfaces and REPLs (Read, Eval, Print Loops).